Preheat the oven to 425 Degrees.
Clean potatoes using a damp paper towel. Rub them thoroughly with 1/2 tablespoon olive oil.
Cover a baking sheet with aluminum foil. Place the potatoes on the baking sheet and bake them for 55-60 minutes or until they are cooked through.
While the potatoes are baking, make the filling.
Place chopped carrots in a small saucepan with 2-3 cups of water and let it come to boil. Cook until carrots are softer, 5-6 minutes.
Drain the carrots and place them into a large bowl.
Place frozen peas in a small saucepan with 1-cup water and cook for 5 minutes or until they are softer. Drain and place them in the same bowl that you put the carrots in.
Add the cornichons, vegenaise, lemon juice, garlic, salt, and pepper. Give it a big stir. Set aside.
Take the potatoes out of the oven and let them cool. Turn the heat down to 350 degrees.
When the potatoes are cool enough to handle, cut them lengthwise and scoop the insides using an ice cream scoop (or a tablespoon). (I use the insides to make mashed potatoes for later.)
Sprinkle potato skins with olive oil, salt, and pepper. Place them on the baking sheet and bake for 10-15 minutes or until the edges of the potatoes turn brown and they are crisp.
Fill each potato half with the filling. Sprinkle them with shredded cheddar cheese, chopped parsley, salt, and pepper.