2. Explain the reasons for and the science behind the following recipe instructions: a) 'Stir the Béchamel sauce all the time whilst it is being heated on the hob. (3 marks)
b) 'Sauté the onions gently until they turn a golden brown colour.' (3 marks)
c) 'Bake the loaf in the oven for 25 minutes until it is well risen and golden brown.' (3 marks)