Preheat oven to 375°F (190°C). Line a baking sheet with parchment paper.
Set up a breading station: Place flour in one shallow bowl, beaten eggs in another, and mix breadcrumbs, Parmesan, garlic powder, salt, and pepper in a third bowl.
Dredge each chicken piece in flour, dip in egg, then coat thoroughly with the breadcrumb mixture. Place on a plate.
Heat olive oil in a large skillet over medium-high heat. Fry chicken pieces until golden brown and cooked through, about 3–4 minutes per side. Transfer to the prepared baking sheet.
Place a spoonful of marinara sauce on the bottom half of each slider bun. Top with a fried chicken piece, then sprinkle with mozzarella cheese.
Bake in the preheated oven for 8–10 minutes, or until the cheese is melted and bubbly.
Remove from oven, top with chopped basil if desired, and serve warm.
Notes
Serve immediately while hot and cheesy for best results.