Preheat the oven to 375 degrees F and line a baking sheet with parchment paper.

Wipe the mushrooms clean with a damp cloth. Use a small paring knife to carve simple skull faces into the caps. Pop out the stems and set the caps aside.

Heat 1 tablespoon of olive oil in a skillet over medium heat. Add the chorizo and cook until it starts to brown and release its fat, breaking it up with a spoon as it cooks.

Stir in the onion and garlic. Cook for 3 to 4 minutes until the onion softens. Add the smoked paprika, a pinch of salt, and black pepper. Remove the pan from the heat.

Mix the shredded Manchego cheese into the chorizo mixture until it melts slightly and binds everything together.

Brush the mushroom caps inside and out with the remaining tablespoon of olive oil. Spoon the filling into each cap, packing it gently.

Place the stuffed mushrooms on the prepared baking sheet. Bake for 15 to 18 minutes until the mushrooms are tender and the tops are golden.

Sprinkle with chopped parsley before serving.