Potato and Vegetable Gratin with Scallions

Rinse bell peppers, peel with a vegetable peeler and cut into bite-sized pieces. Peel onion and garlic and chop finely. Heat butter in a pan and saute onion and garlic until soft, cool. Heat oil in a pan and saute peppers for a few minutes, season with salt and pepper, drizzle with lemon juice and cool. Rinse spinach and blanch in boiling salted water for a few minutes. Place while wet into the pan and saute briefly. Drain in a colander and cool. 

Chop spinach. Combine spinach with half of oinon mixture and season with salt, pepper and nutmeg. Peel potatoes and grate coarsely. Combine potatoes with remaining onion mixture and cheese. Beat eggs with cream and fold into potato mixture. Layer a third of potato mixture in a lined with parchment paper springform pan, spread peppers on top and layer another third of potato mixture.