Prep – Preheat oven to 350°F (175°C) and line baking sheets with parchment paper.
Cream butter and sugars – Beat butter, brown sugar, and white sugar until light and fluffy.
Add eggs & vanilla – Beat in the eggs, then stir in vanilla extract until smooth.
Mix dry ingredients – In another bowl, whisk together flour, baking soda, cinnamon, cardamom, and a pinch of salt.
Add dry ingredients & oatmeal – Pulse the oats in a blender until coarsely ground. Fold the oats and flour mixture into the wet ingredients until just combined.
Shape cookies – Roll dough into 1.5-inch balls and place on baking sheets 2 inches apart. You’ll get around 18-20 cookies depending on how big you make the balls of dough.
Bake – Bake for 10–12 minutes, until edges are golden but centres are still soft.
Cool – Let cookies sit on the baking sheet for 5 minutes before transferring to wire racks to cool completely.