Add butter and sugar to the bowl of an electric mixer. Mix for a few minutes until creamy. Add egg and whisk until pale and fluffy.
Add vanilla, baking powder, salt, flour and semolina. Mix with a wooden spoon until the dough comes together. Use your hand to knead it into a smooth ball.
Divide the dough into 18 balls. Roll each ball in the palm of your hands, slightly flatten it and place it on a lined baking sheet. Place biscuits 2cm apart on the tray.
Using your thumb or forefinger, make indents on top of each biscuit. Using a small teaspoon, fill the indents with jam (about a half a teaspoon in each indent).
Bake for 15-20 minutes until biscuits are done and slightly golden. (I bake mine for 16-17 minutes, turn off the oven and leave them in for another minute or two).
Remove from the oven and cool completely on a wire rack. Store in an air-tight jar in a cool corner of your kitchen for up to 3 days or in the fridge for up to a week.
Notes
Sugar - Use granular sugar. Raw sugar works perfectly in this recipe as it has a slight golden tint that comes through in the biscuits.Semolina - Semolina adds a bit of texture and crunch to the cookies making them slightly crispy as otherwise they tend to soften over time. If you don't have semolina, just leave it out and substitute with extra flour.