Healthy Sandwich

I'd made tuna sandwiches for my brunch today. It's real delicious, simple and healthy. Of course, the most important that it's low in calories. :) So, here I write down the steps to make it.

1. Chunks/ Flakes of Tuna in water, mix with mayonnaise, diced big red onion, a pinch of salt and a little bit of pepper.
2. Salad vegetables (Butterhead lettuce etc) and tomatoes.
3. Spread some butter on the bread (wholemeal bread is recommended because it's healthier) and then the tuna and veges.
4. You can make as many layers as you want. :)