Melt the butter and sugars

• Melt the butter in a saucepan over medium heat.
• Stir in the brown sugar, granulated sugar and milk until dissolved and smooth.
• Remove from the heat and stir in the vanilla extract.

Make the dough

• Whisk the flour, baking powder and salt together.
• Stir the dry ingredients and the rolled oats into the warm butter mixture until a loose dough forms.

Spoon onto the baking sheet

• Preheat the oven to 180 °C and line a baking tray.
• Spoon small mounds of dough onto the tray, leaving plenty of space for spreading.

Bake

• Bake until the cookies are lacy, golden and crisp at the edges.
• Let them cool on the tray until firm.