Spinach, Onion & Feta Oven Omelets

These tasty oven omelets make a great supper on a busy day!  Not only are they quick and easy to make, but they are also very delicious! We love them!

 
You could use frozen spinach for them if you wanted to, but I prefer to use fresh.  Its readily available all year round. I use the ready to eat baby spinach leaves, and I always ...