Combine the almond flour and (2tbsp+2tsp together) of large flake nutritional yeast in a medium-sized bowl. Season chicken breast with salt (optional) and pepper, and then coat both sides with almond mixture.
Bake the chicken for 12 to 15 minutes or until internal temperature reaches 165*F. Once cooked, remove the chicken from the oven and set aside to rest.
While the chicken is baking, combine tomatoes, oregano, garlic, and scallions in a pot and simmer on low for 15 to 20 minutes.
Zucchinis (1 lb. total), cut, sliced, or "spiralized" into noodle-like strands (should yield about 4 cups zucchini noodles). Steam zucchini "noodles" in a steamer basket over boiling water on stovetop until tender.
Serve zucchini "noodles" with marinara and chicken.