Preheat oven to 180°C / 350°F (160°C fan-forced). Grease and line two baking trays with parchment paper, and set aside.
Place the softened butter in a large bowl and add the sugar. Beat the butter and sugar till light and fluffy.
Add the egg and beat for another 30 seconds – 1 minute, till combined.
Add the cardamom powder, followed by the vanilla essence, and combine.
Add the plain flour, and beat on low speed to combine. The dough will be soft, and come together into a large ball shape.
Use your hands or a tablespoon to roll the mixture into small balls (about 2 teaspoons / 1 tablespoon per ball).
Place the cookie balls in the baking tray, making sure that there is 1 ½ inch space between each cookie. Use a wooden spoon, or the back of a chopstick, or your little finger to create an indent in the middle of the cookie.
Use a teaspoon to carefully place a small amount of jam into each indent. Place the trays into the fridge and chill for 15 – 30 minutes. This step is to prevent the cookies from spreading too much.
Bake the cookies for around 8 – 12 minutes until pale golden from top, and the jam has set.
Let the cookies cool on the baking tray for a couple of minutes, and then transfer to a wire rack to cool completely. Dust with powdered sugar before serving. This recipe yields about 40 small cookies, and serving size is based on 2 cookies per serving.