Cuban-Inspired Pork Casserole

0 Season pork shoulder with 1/2 tablespoon coarse sea salt. Place in the slow cooker. Cook on low for 8 hours on low, or about 6 hours on high, until pork easily shreds apart. See here for Instant Pot method.
1 Combine 4 cups shredded pork with remaining seasonings, and taste to see if additional salt is needed.
2 Preheat oven to 400 F.
3 Toss bell peppers with one teaspoon olive oil. Spread out onto a sheet pan and roast for 30-40 minutes, until skins are slightly blackened and wrinkled.
4 Toss cubed plantains with one teaspoon olive oil and 1/2 teaspoon sea salt. Spread out onto a sheet pan and roast for 30-40 minutes, until cubes are slightly browned. These can roast at the same time as the peppers if your oven has room.
5 Once peppers and plantains have finished roasting, reduce the oven heat to 350 F. Toss the peppers in the lime juice and then spread them in an 8x8 pan, top with the plantains, and then top with the shredded pork. Bake for 30 minutes.
6  While the casserole is baking, combine all ingredients for the mango salsa in a medium-sized bowl.
7 To serve, spoon salsa on top of individual servings of casserole.