Clean, wash and finely chop the leek. Peel garlic and chop finely. Cook pasta in boiling salted water for about 10 minutes. Melt the fat in a pot and fry the leek and garlic. Dust with flour and sweat for about 1 minute.
Add stock and white wine while stirring. Bring to the boil and stir in the milk. Let it boil down at medium heat for about 5 minutes. Grate cheese finely, remove pot from heat and add cheese. Melt while stirring. Wash thyme, dab dry and chop finely. Season sauce with cayenne pepper and thyme. Drain noodles and let them drain. Arrange noodles and sauce on plates.
Melt while stirring. Wash thyme, dab dry and chop finely. Season sauce with cayenne pepper and thyme. Drain noodles and let them drain. Arrange noodles and sauce on plates. Sprinkle with thyme and parmesan cheese