Whisk eggs and sugar. Add oil, milk, and cream; mix well.
Sift flour, cocoa, and baking powder; add to the wet mixture with a pinch of salt.
Pour batter into muffin molds, filling halfway.
Mix butter and sugar. Add vanilla and egg; stir.
Add flour; mix until a dough forms. Fold in chocolate chips.
Place pieces of cookie dough on top of muffin batter.
Bake at 180°C (350°F) for 20-25 min (35-40 min for XXL molds).
Cool and enjoy!
