So Simple Ideas
Preheat oven to 375°F then whisk the eggs and milk in a large bowl, then stir in the dill, pepper, and the salt.
To a hot skillet add oil, then add the green onions and garlic and cook, stirring occasionally, until fragrant, 2 to 3 minutes. Add the spinach and cook, stirring occasionally, until wilted, about 2 minutes.
Spread the spinach out and top evenly with the salmon. Pour egg mixture over the top. Then top evenly with the cheese. Increase the heat slightly and cook, undisturbed, until the sides begin to set, 3 to 4 minutes.
Transfer to the oven and bake for 17 to 20 minutes, or until the center of the frittata is firm. Remove from the oven and let sit for 5 minutes before serving.