1. Mix all the ingredients together and chill. This can be made ahead and refrigerated overnight.
For the burritos:
1. Preheat the oven to 350°F. Wrap the tortillas in aluminum foil and warm in the oven.
2. Heat the beans in a small pan or in the microwave until very warm.
3. Break the eggs into a bowl. Add the egg whites, salt and pepper, and mix well with a fork.
4. Heat the oil in a large skillet over medium-high heat. Pour the eggs into the pan and scramble until the eggs are just cooked, about 1 1/2 to 2 minutes.
5. To put it together: Place a spoonful of beans in the center of each tortilla. Divide the scrambled eggs among the tortillas, spooning them over the beans. Spoon a teaspoon of relish on top of the eggs. Roll up the tortillas and place 2 burritos, seam side down, on each plate. Top with more relish and serve immediately.