Prepare the Batter:
In a large bowl, combine the cooked rice, flour, eggs, and milk. Stir well until the mixture is smooth.
Add the grated Parmesan cheese, parsley, garlic (if using), and baking powder. Season with salt and pepper. Mix everything until well combined.
If you’re using any optional add-ins like ham, mozzarella, or corn, fold them into the batter now.

Heat the Oil:
In a large skillet or a deep fryer, heat enough vegetable oil to submerge the fritters over medium heat. The oil is ready when a small amount of batter dropped into it sizzles and browns.

Form and Fry the Fritters:
Using two spoons or a small ice cream scoop, form balls of the rice mixture and carefully drop them into the hot oil.
Fry the fritters in batches, being careful not to overcrowd the pan, until they are golden and crispy, about 3-4 minutes.
Use a slotted spoon to transfer the fritters to a plate lined with paper towels to drain excess oil.

Serve:
Serve the Bolinho de Arroz hot. They are best enjoyed fresh from the fryer while crispy and warm.