For the syrup, wash the lime and lemon hot, grate dry and grate the peel thinly. Put the citrus peel, sugar and 150 ml water in a pot, bring to the boil and let it boil down over medium heat for 4-5 minutes to make the syrup.
Remove from heat and allow to cool for about 30 minutes.
Remove the pomegranate seeds with the back of a spoon. Wash the grapefruit, grate dry and cut off 4 thin strips of skin with a peeler. Halve the grapefruit and squeeze it. Cut the vanilla pod lengthwise and scrape out the pulp with a small knife.
Mix vanilla pulp and grapefruit juice.
Place 4-5 ice cubes in each glass. First pour the citrus syrup into the glasses. Then add grapefruit juice and 2 cl vodka each. Spread pomegranate seeds and 1 grapefruit peel each in the glasses.
Just before serving, fill up with 1 bottle of beer each. Serve immediately.