Start by preheating your oven to 350°F (175°C). This step is crucial to ensure your cookies bake evenly.
In a large bowl, cream together the butter, margarine, and sugar until light and fluffy. This step takes about 3-4 minutes. Add in the egg, corn syrup, and vanilla. Mix until well incorporated.
In a separate bowl, whisk together the flour, baking soda, sea salt, nutmeg, and cardamom. Gradually add this dry mixture to the wet mixture. Stir gently until just combined. You don’t want to overmix, so when you see traces of flour, stop.
In a small bowl, combine caster sugar, cinnamon, and cardamom for the coating. Mix well to ensure even distribution.
Using a cookie scoop or your hands, form small balls of dough (about 1 inch in diameter). Roll each ball in the cinnamon-sugar mixture until fully coated.
Place the coated balls on a baking sheet lined with parchment paper, spaced out evenly. They’ll spread, so give them room.
Bake for 10-12 minutes or until the edges are lightly golden. The centers may appear soft, but they’ll firm up as they cool.
Allow the cookies to cool on the baking sheet for about five minutes before transferring them to a wire rack. Enjoy the heavenly smell wafting through your kitchen!