UK-based Fabio's Gelato has two shops north of London (in the towns of Hitchin and Letchworth, Hertfordshire). Fabio's is a small, family gelato parlor that makes its desserts on-site, "using local ingredients where possible." This is their "WKD Blue Sorbet" creation using a blue Vodka beverage by WKD.
For more boozy ice cream bef-afters, see the first two links below.
To learn more about Fabio's Gelato and WKD, see the 3rd and 4th links.