Tuna Melts with French Flair

In just barely more time than it takes to assemble and slice sandwiches, you can have this delicious tuna melt, to warm you on a chilly day near the coast. Makes 3 or 4:

3-4 slices of multigrain toast (not buttered)
1 can tuna in water, drained, and mixed with
1 diced tomato
15 ml Dijon
15 ml mayonnaise

Preheat broiler to high. Make the filling and put it on the toast. Grate over top, a thin layer of Comté cheese (aged cheddar works well also). Voilà, a satisfying lunch for 2.