Wash the potatoes and cook in boiling water for about 20 minutes. Clean and wash broccoli and cut into florets. Cook in boiling salted water for about 5 minutes. Cut the smoked pork loin into cubes. Wash the thyme, dab dry and chop finely.
Peel onion and chop finely. Drain potatoes and broccoli and chill in cold water. Peel and slice the potatoes. Melt the fat in a saucepan. Sauté onion and thyme in it. Sprinkle with flour and sweat while stirring. Gradually add 250 ml water and milk while stirring. Bring to the boil, stir in broth and simmer for about 5 minutes. Add cheese and let it melt in it. Season to taste with pepper.
Sprinkle with flour and sweat while stirring. Gradually add 250 ml water and milk while stirring. Bring to the boil, stir in broth and simmer for about 5 minutes. Add cheese and let it melt in it. Season to taste with pepper. Layer potatoes, broccoli, smoked pork loin and sauce in an ovenproof dish. Sprinkle with Gouda and bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 20-25 minutes