Clean, wash and cut broccoli into small florets. Cook broccoli in boiling salted water for about 15 minutes. Melt the fat in a pot, dust with flour, sweat it on and gradually deglaze with broth and cream. Bring to the boil while stirring and season with salt and pepper. Grate cheese coarsely.
Drain broccoli well on a sieve. Layer sauce, lasagne sheets, ham, broccoli in an ovenproof dish and layer all ingredients again in the same order. Finally, add the sauce and sprinkle with the cheese. Bake in the preheated oven (electric cooker: 200°C/ gas: level 3) for approx. 45 minutes. Serve lasagne garnished with thyme as desired