Preheat oven to 400 F.
Place rack in middle of oven.
Whisk eggs together in a medium bowl and stir in parmesan, gruyere, salt and pepper. Set aside.
In a small cast iron skillet, heat up olive oil over low heat.
Add Brussels sprouts and shallot, saute until shallots soften and Brussels sprouts begin to caramelize.
In a medium pot, boil salted water and add peas. About 2 minutes.
Remove and drain peas. Set aside.
Add minced garlic and saute for 40-45 more seconds.
Add peas to pan.
Pour egg mixture you set aside into pan and ensure that all ingredients are evenly distributed.
Cook for 60-75 seconds or until you see the edges start to set.
Place skillet in oven and bake until eggs set. About 15-17 minutes.