Preheat oven to 400F and place a 24-muffin tin or silicone mold on a baking sheet. (You can also use a 12-muffin tin or mold to make larger pizza bites.)
Dice the pepperoni slices and optional jalapeño slices and mince the garlic. Add the pepperoni, jalapeño, and pineapple to a skillet over high heat. Cook until the pepperoni is crisp before adding the minced garlic, about 3-5 minutes. Cook for an additional 30-60 seconds before removing from the heat.
While the pepperoni cooks, add the pizza bite mixture ingredients to a large bowl and stir well.
Add the pepperoni mixture to the pizza bites mixture and stir well.
Spoon the mixture into the muffin mold, filling each all the way full.
Bake for 24-28 minutes or until the pizza bites are cooked through. Let them cool for 20-30 minutes before digging in.