In a medium bowl, add the eggs and ½ teaspoon salt and whisk thoroughly. In a large skillet over medium-high heat, add 1 tablespoon oil. Once hot, add the eggs and use a rubber spatula to pull the outer edges in to form curds and gently scramble. Repeat until almost cooked through, about 1 minute (eggs will continue to cook). Remove from heat and transfer back to the bowl and cover with a cloth or lid to keep warm. Wipe out the skillet.
In the same skillet over medium heat, add remaining 1 tablespoon oil, white parts of scallions, and ¼ teaspoon salt. Cook for 3 minutes, stirring occasionally, or until softened. Add the veggies and ¼ teaspoon salt and cook until tender, about 5 minutes. Stir in the beans, spices, and remaining ¼ teaspoon salt and cook for 30 more seconds, stirring constantly (this toasts the spices). Remove from heat and stir in the tomatoes (if using).
Make the sauce by adding all ingredients to a blender and blend until smooth.
Warm up your grains or your tortillas. Add eggs, bean/veggie mix, and top with sauce and pickled red onions (if using).