Place bell peppers onto a baking sheet, drizzle with olive oil, and toss to combine. Spread peppers evenly across the pan.
Bake in the preheated oven for 20-25 minutes until the skins start to char and blister, flipping once in between. Remove and set aside.
Bring a large pot of water to a boil. Add potatoes and cook for 10-15 minutes or until soft. Drain the water and place in a bowl.
Mash the potatoes with a masher or fork, leaving some small chunks—you don't want them thoroughly mashed.
While the potatoes are hot, stir the butter until thoroughly melted, then add the half and half. You may need more or less depending on the size of your potatoes.
Add salt and pepper to taste.
Fold in the cooked peppers.
Gently mix in the mozzarella
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