Directions

1. Adjust oven rack to center position; preheat oven to 400 degrees. Lightly grease or vegetable spray a 9-inch heat-resistant glass dish and set in heating oven.
2. Heat oil in a medium skillet over medium-high heat. Add onions and cook, stirring occasionally, until soft, about 5 minutes. Stir in garlic and cook until fragrant, about 1 minute. Add spinach and continue cooking until all moisture has evaporated. Remove from heat.
3. Combine eggs, cheese, salt and pepper in a large bowl. Stir in spinach mixture.
4. Carefully remove glass dish from oven. Pour in spinach mixture and bake until set, about 25 minutes. Cool slightly, slice and serve.