Separate the onions into rings. To extract moisture sprinkle with 2 t of salt and stirring now and then, let them  sit for about 20 minutes. Dry between 2 layers of paper towels.

In a large skillet heat 3 T of olive oil and add the onions. Cook on medium-high heat about 20 minutes until onions are golden and caramelized. Season well with lots of salt and pepper. Set aside.

Cut 2 potatoes into chunks and add to boiling salted water and cook until soft. Drain and place in a large bowl and mash with a large fork or potato masher. Add half of the onions and stir in.

Preheat oven to 400 with one rack in the top position. In a food processor fitted with the shredder or using a grater, shred the rest of the potatoes. Place in a colander and rinse well with cold water to remove the starch. Squeeze out as much liquid as possible and add to the mashed potatoes.

Beat the eggs until thick and light and add the baking powder. Mix well and add to the potato mixture. Check for seasoning because you may need to add more salt and pepper.

Pour 3 T of olive oil into a large oven proof pan-preferably a metal pan or a cast iron. Rub the oil all over and place in the preheated oven for 5 to 10 minutes until sizzling hot, but not smoking. Transfer potato mixture to the pan and spread evenly. Top with the remaining onions. Sprinkle with your choice of herb, if using and then sprinkle with more salt and pepper and a drizzle of olive oil.

Place back in oven on the top rack and bake for 30 minutes. Then turn down oven to 350F and bake for 25 to 40 minutes until the kugel is firm and crispy. Let kugel cool until it is ready to be sliced.