For the pickled carrots: Heat the vinegar, sugar, salt and 1 cup water in a small saucepan over high heat and bring to a boil. Place the sliced carrots in a large mason jar. Pour the hot pickling liquid over the carrots and let cool. Refrigerate, covered, at least 30 minutes and up to 10 days.
For the red pepper stew: Warm the olive oil in a large Dutch oven over medium heat. Add the peppers, tomatoes, onions and salt and cook until the vegetables are softened, about 15 minutes. Add the tomato paste and continue to cook for 3 to 4 minutes, stirring frequently. Add the sweet paprika, hot paprika, 2 cups water, sugar and red wine vinegar. Bring to a boil, then turn off the heat and let cool 5 minutes.
For the gefilte fish: Heat a splash of olive oil in a large skillet over medium heat. Saute the celery, onions and peppers with the salt until the vegetables are slightly softened and translucent, about 5 minutes. Transfer the vegetables to a large bowl, stir in the white pepper and let cool to room temperature, about 10 minutes.
Meanwhile, pulse the bass in a food processor three to six times until it is coarsely chopped. Add the fish to the bowl with the vegetables and mix together by hand to incorporate. Add the matzo meal, dill, parsley and eggs and mix to combine.
Add two large spoonfuls of the red pepper stew to the bottom of a baking dish to keep the fish from sticking. Using wet hands, form the fish mixture into about sixteen 2-ounce patties that are about 2 inches in diameter and place them in the baking dish. Spoon the red pepper stew over the gefilte fish, then sprinkle the chopped olives over top. Bake until the fish is cooked through, about 30 minutes.
Serve the gefilte fish at room temperature. Garnish with the pickled carrots, a squeeze of fresh lemon juice, olive oil, fresh dill and cilantro and the espelette pepper.
Be sure that the white vinegar is certified kosher for Passover as some are made from wheat.