Fill a large pot with enough water to blanch peppers. Bring it to boiling over high heat. Using a sharp knife, cut off long triangles on one side of the peppers and reserve them. You can remove the seeds before or after the blanching. Add salt to the boiling water to make it sea-salty. Blanch peppers for 3-5 minutes making sure they are submerged.
Prepare a baking sheet lined with parchment paper. Arrange blanched and strained peppers on the paper and let them cool down to the room temperature while you are making the crab stuffing.
Dice reserved pieces of Hatch. In a skillet, heat 1 tsp of olive oil over medium heat, season and saute diced Hatch until soft.
Combine breadcrumbs, eggs, mayo, mustard, and parsley. Add sauteed Hatch and picked crabmeat and gently mix. Stuff peppers, cover with plastic wrap and refrigerate for at leat 30 minutes.
Preheat oven to 400F. Brush the top of the stuffing with some oil or mayo and bake for 35-40 minutes until light caramelization. Serve hot!