Preheat oven to 500°F.
Cut the mushrooms in 1/4” slices.
Lightly brush a rimmed baking sheet with olive oil.
Spread the mushroom slices onto the sheet in a single layer.
Brush with the rest of the olive oil and grind some pepper over them. Bake for 6 minutes.
Turn the mushroom slices over and continue baking for another 6 to 8 minutes until the slices are golden-brown at the edges.
While the mushrooms are cooking, mix the mayonnaise, lemon juice and paprika.
Arrange the mushrooms in a row across the bottom third of the tortillas.
Spread the mayonnaise on top of the mushrooms (about 2 tsp of mayonnaise for each tortilla).
Top with the mozzarella slices and sprinkle pepper to taste.
Top with peppers and the baby spinach leaves.
Roll each tortilla, cut in half and serve.