Meanwhile, mince the chicken. I do this in the small food processor attachment that comes with the hand blender. Add it to the onions.
3 chicken thigh fillets
Preheat the oven to 200 degrees.
Once the chicken is fully cooked, drain off the excess fat and liquid. You can use a colander or sieve for this. Then return it to the pan and mix in the tomato paste.
140 g tomato paste
Drain the mushrooms as well and pat them dry with kitchen paper. Then return them to the pan. Crumble in the Roquefort. Let it melt over a low heat.
150 g Roquefort
Grate the Pecorino. Divide it into 5 portions. If using arrowroot, mix it into 4 portions of the cheese. One portion is for the top. There is no need to add arrowroot to that one.
125 g Pecorino, 3 teaspoons arrowroot
Sprinkle the first portion of cheese (mixed with arrowroot, if using) over the bottom of the loaf tin.
Put half the chicken in the loaf tin. Sprinkle with another portion of cheese (with the arrowroot).
Lay a third of the pumpkin sheets on top. They do not need to fit together perfectly or cover everything. I usually leave a gap in the middle as well. This makes it easy to divide into two portions.
250 g pumpkin lasagne sheets
Spoon half the mushrooms with blue cheese on top. Sprinkle with another portion of Pecorino and cover with another third of the sheets.
Then add a second layer of chicken, and cover again with cheese and sheets.
Then add the final layer: the mushrooms, topped with the last portion of Pecorino (this one has no arrowroot).
Bake for 25 minutes.
Let cool a little before serving. A flat spatula is best for serving. Without arrowroot, the lasagne will be a little wetter and a little less firm.
Notes
Equipment: large PFAS-free frying pan, loaf tin (or a narrow, deep baking dish), sieve or colander, kitchen paper, (small) food processor.