Italian Macaronie And Cheese

• 2 garlic (cloves)
• 1 onion (chopped)
• 475 ml milk
• 190 gr mild
• 190 gr shreeed jack cheese
• 110 gr elbow macaroni
• 80 gr thinly mushrooms (sliced)
• 60 gr parmesan
• 32 gr flour
• 28 gr butter