• 1 piecrust
• 4 slices bacon, cut crosswise into ¼-inch slices
• 6 cups baby spinach
• 1½ pounds yellow onions (about 4), halved and cut crosswise into ¼-inch slices (6 cups)
• ¾ teaspoon salt
• ¼ teaspoon dried thyme
• 3 eggs
• ¾ cup half-and-half
• ¼ teaspoon black pepper
• ¼ cup shredded Gruyere cheese

1. Heat oven to 375°F. Fit piecrust into 9-inch tart pan. Trim excess crust from top edge of tart pan; refrigerate while preparing filling.
2. Heat a large nonstick skillet over medium heat. Add bacon to skillet and cook, stirring often, for 8 minutes. Add spinach to skillet and cook 1 minute, stirring until wilted. Using a slotted spoon, remove bacon mixture to a paper-towel-lined plate.
3. Return skillet to medium heat and add onions, ¼ teaspoon salt and the thyme. Cover and cook 25 minutes over medium heat, stirring occasionally, or until browned. Remove from heat and allow to cool, uncovered, 5 minutes.
4. Whisk together eggs, half-and-half, pepper and the remaining ½ teaspoon salt. Stir bacon mixture and onions into eggs; stir to combine. Pour egg mixture into crust. Bake at 375°F for 15 minutes. Reduce heat to 325 degrees F and continue to bake 20 minutes.
5. Heat broiler. Sprinkle tart with Gruyere and broil for 1 to 2 minutes. Let stand 5 minutes before slicing and serving.

Makes: 8 servings