Sausage, layered potatoes & tomato sauce

Then, I try to do one new dish each week and this was layered potatoes with onion, garlic and a little milk and cheese. I was in a rush so didn't pre-cook anything. I just sliced the spuds, added onion cut into rings, bunged on some grated cheese and a bit of garlic powder, poured some milk with mustard stirred in, added some oat bran to thicken and whacked in the oven. It turned out way better than expected and the boys raved. Only issue was length of cooking time that I seriously underestimated.
Max particularly singled out the onions (YES) and they did give it a je ne sais quoi!
I added some home-made rich tomato sauce. No chance of that not being scoffed!