Preheat oven to 350 degrees. Wash potatoes, place them on a baking sheet and cook for 1 hour. Remove from heat and allow to slightly cool.

While the potatoes are cooling, heat the olive oil in a saucepan over medium heat. Chop the bell pepper and spinach and mince the shallot. Add the shallot and cook for 2 minutes. Add the bell pepper and cook for 5 minutes. Add in the spinach and cook just until wilted, then remove from heat and place the mixture in a bowl.

Slice the potatoes lengthwise, and use a spoon to scoop out the potato flesh - leaving a bit of potato around the skins so that they mostly retain their oval shape. Mash the potatoes until mostly smooth, and place in the veggie bowl.

Shred your cheese, and add it to the veggie bowl. Add in the butter, salt, and pepper, and mix until evenly combined.

Spoon the potato mixture back into the potato skins on the same baking sheet. Cook for 20 minutes, or until the cheese is melted and the potato are starting to look lightly browned.

Serve with your favorite potato toppings!