Preheat oven to 180°c and line 2 x baking trays with baking paper.
Beat butter, sugar, and vanilla in a bowl using an electric mixer until light and creamy.
Add egg and mix until well combined.
Sift flour and baking powder over butter mixture.
Add milk and stir until just combined (I used a dough hook on my electric mixer for this part).
Add 2-3 tablespoons sprinkles to the dough and mix until combined.
Using 1 heaped tablespoon or an ice cream scoop to roll the mixture into balls. Push down the cookie dough ball to flatten in a bowl of sprinkles.
Put the biscuit on a lined baking tray and push down further to flatten the biscuit with a spatula (allow room for spreading).
Bake for 12-15 minutes or until they are lightly brown (don’t overcook or they will be dry).
Transfer biscuits to a wire rack to cool.
ENJOY!