Preheat the oven to 200C. Line two or three baking sheets with baking paper. Place butter and sugar in mixing bowl. Beat until pale and well combined. Add almond meal, beaten egg and 4-5 drops of almond essence. Sift in flour and baking powder. With a large metal spoon, fold and combine to a smooth, buttery dough.
Roll heaped teaspoonfuls between your palms and place on baking paper. Space well apart. Make a well in each with a pea-sized round knife handle (or your little finger), pressing each sphere down slightly. Fill with a small dab of jam, then top with a few slivered almonds. Bake for 10 minutes. Transfer to wire racks to cool completely before storing in airtight containers. These biscuits will firm when cooled.