What you'll need
This drink is, of course, designed to resemble the two coloured portals from the excellent sci-fi puzzle game. For the blue version, get a small tumbler and pour in 10ml of Blue Curacao, 10ml of vodka and top up with lemonade. For orange you'll need another tumbler, this time filled with 10ml of Cointreau, 10ml of rum and Orangina. If you fancy, you can jazz the glasses up with coloured sugar rims. Simply pour some sugar into a sandwich bag with the relevant food colouring, shake them up, pour the resulting mix into a dish and dip your tumbler in. "You can mix the portals together if you like," says James. "It's a very orangey flavour, which we thought tied in with The Orange Box, the compilation in which the original Portal appeared."
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