Preheat oven to 350 degrees F (175 degrees C). Grease a baking sheet lightly.
Beat sugar, butter, and coconut oil together in a large bowl with an electric mixer until light and fluffy. Beat in egg yolks and vanilla extract. Add flour, baking powder, and baking soda gradually; mix until dough just comes together. Mix dough with hands to fully incorporate ingredients. Roll dough into walnut-size balls and place 2 inches apart onto baking sheet.
Bake in the preheated oven until cookie tops are cracked, 10 to 12 minutes.
Parchment paper can be used in place of greasing the baking sheet, if desired.
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