150 ml gin

350 ml Indian tonic water (containing quinine)

A splash of rose water (optional)

5 leaves of gelatine

Glowing, quivering and looking more like an alien invasion than something you should put in your mouth, gin & tonic jelly (jello for those in North America) packs a real punch.Inspired by Bompas & Parr (the Blumenthal' s of the jelly world) this uses the naturally flourescent quinine in Indian tonic water to make a luminous loaded dessert. All you need is some simple ingredients, a bit of patience, and a UV light to show the whole thing off.Ingredients (makes 500 ml of jelly) :You'll also need a measuring jug, small saucepan, heatproof bowl, seive and a jelly mould, preferably metal since this is best for releasing the jelly. I used an aluminium castle cake tin.First, measure out the gin, tonic & rosewater into a jug. Cut the gelatine leaves into a small pieces and put them in your heatproof bowl with enough of the G&T mix to just cover them. Leave this for about ten minutes until the gelatine has absorbed the liquid and is soft and floppy.Place the bowl over a saucepan of boiling water (just an inch or so of water to create a double boiler, making sure the water doesn't touch the bottom of the bowl). Heat the gelatine, stirring occasionally, until it melts and you have a clear liquid. Take the bowl off the heat and strain the gelatine to catch any lurking lumps. Pour in the rest of the G&T mix and stir briefly to combine.Pour the jelly into your mould. Put the mould in the fridge and allow the jelly to set. This takes around 5 hours, until the jelly is wobbly but not sticky on top and doesn't slip at the sides if you tilt the tin. I left mine overnight to be safe.When set the jelly can be unmoulded. Run a small knife around the edges of the mold to loosen it and then dip the mold in warm water for about 10 seconds, to melt the very outer layer of the jelly and help it slip out. Place a flat plate on top of the mould, invert the whole thing, and liftthe mould up, shaking it a little if the jelly is sticking. It's best to moisten the plate a bit before turning out the jelly onto it, as this stops it sticking immediately and lets you reposition it a little for perfect presentation.To get the full impressive effect, serve the jelly in a dark room lit with a blacklight and watch it glow!(Beware, this is a strong jelly, the very essence of a stiff G&T. It's perfect for jelly shots but if you're serving larger quantities I'd substitute a little of the tonic for a simple sugar syrup to take some of the edge off.)