For the pesto, roast the almonds in a pan without fat for about 3 minutes while turning, remove. Wash the lemon balm, shake dry, pluck the leaves from the stalks and chop. Mix lemon balm, oil, sugar, rum and sambal oelek.
Chop the almonds and stir them in. Peel pineapple, cut into 6 slices. Halve the slices and cut out the stalk. Grill the pineapple slices on a grill or grill pan on each side for about 3 minutes.
Arrange pineapple and pesto on plates.