Preheat oven to 375°F (190°C). Grease mini muffin cups.

Combine first 5 ingredients in a medium-sized bowl. Stir well.

In another bowl, whisk together egg, milk, and oil. Pour into dry ingredients and stir well just until moist. Add olives, stir to combine.

Spoon batter into prepared muffin tins. Sprinkle with remaining 1/2 cup Parmesan cheese. Bake in preheated oven for 15 minutes or until a toothpick inserted into center of muffin comes out clean.