A Ottolenghi style variant.
Ottolenghi Italian sausage lasagne

Ingredients
2 tbsp olive oil
350 g Italian sausages
200 g kale ( or cavolo nero )
5 small roasted peppers
1 tbsp olive oil
2 garlic cloves
500 g tomato pasatta
2 tsp sugar
100 ml milk
100 g ricotta
100 g cream cheese
75 g parmesan
12 lasagne sheets
70 g gruyere cheese
60 g roasted hazel nuts
Method
Heat the tablespoon of oil and fry the garlic (crushed) for a minute. Add the passata, sugar and simmer for 10 minutes.
In a large pan add 2 tablespoons of olive oil and the inners of the inners of the Italian sausages and saute for ten minutes. Add the kale leaves roughly chopped, cook for ten minutes until wilted. Stir in the caraway and cook for 5 minutes more.
Place the milk, ricotta, cream cheese and parmesan in a small pan and heat to mix to a creamy texture.
Heat the oven to 180 C. Grease the lasagne dish (about 35cm x 25cm) with some oil, then cover the base with four sheets of lasagne. Cover these with third of the tomato sauce, then spread half the sausage mix on top. Pour over half the cheese sauce, then repeat for another layer, finishing with a layer of lasagne.

Cover with the final tomato sauce, grate over the Gyuyere and sprinkle over the hazelnuts. Bake for 35 minutes, until bubbling and golden.