Pre-heat oven to 305 degrees.

Heat the oil in a large ovenproof skillet over medium-high heat. Sauté onions and garlic until onions begin to sweat.

Add kale, mushrooms, and tomatoes and cook until kale is tender. Reduce heat to medium and add a little salt and pepper to taste, if you desire.

In a mixing bowl, whisk together the egg whites, almond milk, baking powder, salt, and pepper, and pour over the vegetables in the skillet. Cook, without stirring, until the bottom of the eggs are frim. This may take about 4–5 minutes.

Transfer skillet to oven and bake until edges are slightly brown, about 10 to 15 minutes. You'll know it's done when a knife inserted comes out clean.

. Sprinkle Feta cheese over the frittata, and if you’re feeling fancy and maybe a little “EXTRA” like me, sprinkle a little rosemary over the top as well! Enjoy! Slice into 4 equal slices to serve.