Preheat the oven to 350°F and prepare two parchment-lined sheet trays.
In a bowl, whisk together the ranch seasoning and melted butter until combined.
Layer prepared sheet trays with Ritz crackers and drizzle with butter mixture. Top each cracker with grated mozzarella.
Lay pepperoni slices evenly on the other prepared sheet tray.
Bake the crackers and pepperoni for 15 minutes on the top rack of the oven, until the cheese is melted and the pepperoni is crispy.
Dollop each cheesy cracker with marinara sauce, then top with crispy pepperoni. Enjoy!
