I don't see this working too well. Assuming the bacon you're using is raw because bacon takes way longer to render than the 3/4 minutes it takes to cook eggs perfectly (I would assume either the eggs would be super overcooked or the bacon would be super chewy). The better way to do this would be to:
1. Lace the cups with bacon first and then throw it into the over for 10/15 min at a low temp.
2. Then add egg mixture with spinach. You can raise temp to about 300 or so for 4/5 minutes. This should have everything cooked perfectly.