Preheat the oven to 200°C (392°F) and position the rack in the middle.

In a mixing bowl, whisk together the eggs, salt, pepper, and any additional seasonings until well combined.

Add the grated zucchini, diced red capsicum (if using), and grated cheese to the egg mixture. Mix well to combine.

Gradually add half of the all-purpose flour to the mixture and stir until combined.

Add the remaining flour along with the baking powder. Mix until the batter is well combined and no lumps remain.

Grease the muffin tin with butter to prevent the muffins from sticking.

Spoon the zucchini mixture into the muffin tin, filling each cup until almost full. This recipe should make approximately 9 muffins.

Bake in the preheated oven for 25 minutes, or until the muffins are golden brown and a toothpick inserted into the center comes out clean. Oven times may vary, so check for doneness starting at 20 minutes.

Remove the muffins from the oven and let them cool in the tin for a few minutes before transferring to a wire rack to cool completely.