I have made macaroni au gratin for dinner.

I like to put some tomato on it before baking.

 

Santoku knife is good for cutting the onion slices.
Using a sharp knife means you can prepare onions easily with no tears.
The weight of the blade cuts straight through the onion leaving the layers intact.

The Santoku knife is the knife most commonly used in Japanese homes. As long as you have one, you can handle any ingredient that comes your way, from vegetables to meat and fish. How about to get one?