I use a 10 inch cast iron pan for a 3-4 person meal and preheat the oven to 350 degrees. Chop vegetables you decide to use in successive layers–here I chose a green mixture of fennel, green peppers, mixed chopped greens, and some orange and yellow peppers.
Sauté two medium onions in olive oil. I like slicing onions in sections end to end after halving. ONIONS IN THE BOTTOM LAYER IS KEY–it will keep the torta from sticking to the pan and crisp and flavor nicely.
After the onions begin to brown continue cooking (on med or med low) and add subsequent layers.
Spread the mix of orange and yellow peppers on top of the potatoes; add the mix of fennel and greens to the second pan and sauté briefly. Spread the green layer on top of the yellow and orange peppers.
I added 2 ounces of Trader Joe’s crumbled goat cheese to the top of the green mix (feta would be good, too). Whisk 5 large eggs in a bowl with a splash of milk or water; 6 eggs if no added liquid. Pour evenly over torta (I use a silicone brush to spread it after pouring).
While the torta cooks on the stove top, chop zucchini in 1/2 inch slices and very briefly sauté in the second pan. I cook the torta on medium low for about 5 minutes on the stove top after adding the eggs, then finish in the oven until the eggs are set (5-10 min).