Preheat oven to 375°F (190°C). Grease a mini muffin tin or line a baking sheet with parchment paper.
In a medium saucepan, melt the caramel over low heat, stirring constantly until smooth. If using caramel squares, add a tablespoon of milk or cream to help it melt smoothly.
Remove from heat and gently fold in the diced apples, coating them evenly with the melted caramel. Add a pinch of cinnamon, nutmeg, and salt to the apple-caramel mixture. Stir to combine.
In a separate bowl, combine the rolled oats, flour, brown sugar, cinnamon, and nutmeg. Whisk together to ensure the spices are evenly distributed.
Cut in the cold butter using a pastry blender or your fingers until the mixture resembles coarse crumbs. Stir in the chopped nuts, if desired.
Spoon the caramel-coated apple mixture into the prepared muffin tins, filling each cup about three-quarters full. If using a baking sheet, create small mounds of the apple mixture.
Sprinkle the crisp topping evenly over the apple filling, ensuring each bite gets a generous amount of crunchy goodness. Gently press the topping down to help it adhere to the apples.
Bake in the preheated oven for 20-25 minutes, or until the topping is golden brown and the apple filling is bubbly. The baking time may vary depending on your oven.
Let the bites cool in the muffin tins or on the baking sheet for a few minutes before transferring them to a wire rack to cool completely. This allows the caramel to set slightly.
Serve the Caramel Apple Crisp Bites warm or at room temperature. Drizzle with extra caramel sauce or top with a scoop of vanilla ice cream, melted chocolate, or chopped nuts, if desired.
