Having just arrived home in the Capital and facing a 10 day post-travel isolation period when we speak, the 54-year-old laughs that distinctive laugh as she shares the secret. "Oh my god! It's gin and ancho verdi, which is a very, very potent Mexican liqueur, and then you have a sort of salty, chill rim around the glass. Definitely have no more than three at a time or it could end badly... and that's all I'm going to say."
Mind Eraser's feature in the album notes for Uncomfortable Me, the third track on No Gods No Masters, which is released on June 11. It’s the seventh studio album from Garbage, the band Shirley joined 25 years ago having previously been a member of much loved Edinburgh bands Goodbye Mister Mackenzie and Angel Fish. The most political album the four piece have ever made, the 'DNA of its content' lies in 'the seven virtues, the seven sorrows, and the seven deadly sins,” says the singer, adding, "It was our way of trying to make sense of how fu**ing nuts the world is."
The 11 tracks on the album range in tone from outrage to vulnerability and even tongue in cheek. All evoke a raft of personal memories for the singer who was raised in the Stockbridge area of the Capital, including the aforementioned Uncomfortable Me, which boasts a catchy hook and has the potential to be a massive anthem.
"Oh, you're sounding like the record company now," she quips.
Described as a 'deceptively tranquil paean to outsiderdom', Shirley herself considers it, "probably one of the most vulnerable songs we've ever recorded".
She explains, "A lot of people have expressed their keenness for that song, it's very universal, that feeling of not really fitting in anywhere. It was something I felt when I was very young and something I still experience even now; I'm a Scottish person living in America. In America I'm considered Scottish. I'm in a band of three older men. I am the youngest member and also the only woman in the band.”
The song was born out of a jam session in Palm Springs and a night on those dreaded Mind Erasers: 'We were drinking these cocktails... I’d drank around three of them, which is really ill-advised, by the time we finished writing the song. It’s my most unguarded self,' she writes in the album notes.
Her most unguarded self, translates to being a misfit, she says. "I guess I am going to be permanently on the outside. It's just the way it's going to be for me. Those feelings of not fitting in used to hurt me a lot but I now realise they give me great independence and autonomy and I'm perfectly happy being on the outside looking in."
It’s a good place to be as a songwriter and on No Gods No Masters, Shirley and the band explore concerns close to their hearts.
"There are things I’ve been increasingly concerned about as I've got older,” she reflects. “The problems I talk about on this record have been around for centuries but I was surprised how increasingly prescient the record became the more time went on. As we were finishing it, I couldn’t believe how it was almost a foretelling of what was to come. It was intense. We made the right record at the right time and it feels so good to have made something that speaks to these times."
She continues, "It's a public testimony and it feels so good to have that platform, to be able to release a record to the public that states your position. It's a lovely, lovely, luxury and a privilege and not something I take for granted. At the same time, I'm not the kind of person who expects of myself to be able to fix global problems. I have accepted I am but a blade of grass and as powerless as the next person. Yes, I'm a musician and, yes, people ask my opinion every now and then, but we are as powerless as anyone. However, as you get older you do feel like you want to make things a little better for the generations that are to follow. You don't want to leave you're room in a mess. So I feel a little pressured to leave things in a better state than we inherited them."
Despite addressing such universal themes, Shirley still doesn't consider Garbage to be a political band, "I’m uninterested in politics for the most part. I see things from a humanitarian standpoint and that is about it," she states.
Travelling the globe for the last quarter of a century has, however, given her a unique view of the world and its problems.
"It definitely gives you a different perspective. We get to travel the world and meet all kinds of people; all colours, all creeds, all genders. It is an extraordinary rich experience that has molded my world view for sure, but I feel grateful to be an outlier, in that Garbage has never really fitted in anywhere in the musical scene. We've always been treated with great suspicion, we’re not poppy enough to fit in with the pop stars, not cool or obscure enough to fit in with the indie scene, we've sold far too many records to be thought of as alternative, so we are just this floating entity that has surprised everybody by still being here making records 25 years on. Every one of us used to find that frustrating, now we realise it has helped preserve our career."
A decade and a half ago, however, there was a time when Shirley feared that career had come to a premature end. That moment when, having just turned 40, she found herself at her lowest ebb is recalled in a track called, The Creeps.
"When you are a woman you’re much more sensitive to the passing of time because you’ve been taught, from as soon as you can absorb information, that women's tenure in the world is under threat at all times, for inexplicable reasons. We exist under patriarchal law and, traditionally, women haven't be able to enjoy long careers. I'd say there has only been one generation of female musicians who have been able to sustain careers past their so called sexual peak. Historically they have been thrown on the dumpster once they pass 30.
"That is all changing now thanks to the generation of musicians that preceded me, Patty Smith, Chrissie Hynde, Debbie Harry, Stevie Nicks… These amazing women are the first to sustain long careers in music and it's glorious and encouraging, but when I got dropped by Interscope Records around my 40th birthday, I was utterly devastated. I got told by my lawyer and was trying to be brave. I got into my car and was driving home when, five minutes from my house, I spotted a yard sale and there, propped up against a lamp post, was a massive shop poster of me and the band with a yellow for sale sign. It was being sold for three bucks.
"There was something about that visual that, compounded by the information I'd just been served, crushed me. For the first time in my life I felt ashamed of myself. I felt like a loser, like I'd messed up my career and my whole life. That was the lowest moment for me.
"But from the moment I saw that poster, I rebuilt myself. I realised I had to keep being creative and that it didn't matter if I was successful or not as long as I was still creative.
“With that realisation I was reborn in the music industry and became immune to all the expectations that had been piled on me and all the pressures that had been put on the band. That was a really empowering moment.”
She learned an important lesson that day, she reflects, “You mustn't listen to your feelings. That is what I talk about in The Creeps, just because you're feeling something, doesn't make it fact and you are never over until you stop trying, so if you keep trying, you are never over."
In part two tomorrow: Shirley fulfills a life long dream... as she sleeps
No Gods No Masters can be pre-ordered here