In a mixing bowl, add Caster Sugar (3/4 cup), Butter (200 gram) and Vanilla Extract (1 teaspoon). Beat with electric mixer until creamy.
Add Egg (1). Beat in until smooth.
Sift in All-Purpose Flour (2 cup) and add Sprinkles (1/2 cup). With a spoon, gently mix together until everything is combined.
Transfer the dough to a lightly floured surface. Shape it into a 30-centimeter log and wrap the log in plastic wrap. Place in the fridge for 1-2 hours to firm up.
Slice the log into 1-centimeter pieces and arrange cookies on a baking tray lined with non-stick baking paper.
Bake at 180 degrees C (350 degrees F) for 10-12 minutes, or until golden.
Allow cookies to cool for 5 minutes.