Clean and wash the cauliflower and cut it into small florets from the stalk. Peel the garlic cloves and cut into fine strips. Peel and finely chop the onion. Wash thyme, shake dry and remove leaves.
Wash the lemon hot, grate dry and grate the rind with a fine grater.
Heat 2 tablespoons of butter in a large saucepan. Stir-fry the garlic and onion until golden brown. (Garlic must not get too dark, otherwise it will become bitter!) Deglaze with 600 ml water and Pale Ale (drink the rest of the beer on the side!).
Stir in broth. Add 350 g cauliflower and thyme. Bring everything to the boil and simmer for 20-25 minutes.
Meanwhile grate the cheese. Add milk and cream to the soup, simmer for 8-10 minutes. Then puree everything with a hand blender. Stir in cheese and mustard. Simmer for about 2 minutes while stirring until the cheese is completely melted.
Keep soup warm at low heat. Heat 1 tablespoon of butter in a frying pan. Fry the rest of the cauliflower for 2-3 minutes, turning it over. Season with salt and pepper. Drain on kitchen paper.
Season garlic soup with salt and pepper to taste. Serve with roasted cauliflower and lemon peel. Good.