My wife calls this simply cheese on toast. She has eaten it for breakfast, more days than not, all of her adult life. And since I was the weekend breakfast cook when the children were young, I learned how to it right.
An open-face, grilled cheese sandwich is oven grilled and better than a pan-grilled chesse sandwich, in my view, because it is not pan-fried greasy, and better than bruschetta, in the winter anyway, because the hot bread and cheese is cooked and blended.
Okay, here are the ingredients.
Slice of Bread.
Preferably fresh bread that can be sliced thicker the normal store-bought, sliced bread but a quality pre-sliced is okay, too. I like the bread about 1/2" - 3/4" thick. I like whole wheat bread because the density of the bread suits and carries the melted cheese well.
We use sharp cheddar. I am sure other kinds of cheese will work as well, but some of them don't oven grill well. I have tried other cheeses when we were out of cheddar, and they tended to brown too quickly on the exterior.
1. Lightly toast the bread in a normal toaster. Lightly, not toasted-through crispy.
2. Slice the cheese. On a 3 inch block of cheese, the slices are about 1/8" thick and you need about 4 - 6 slices.
3. Place the toast on a cookie sheet or piece of aluminum foil and layer the cheese on the toast. Important: Make sure that the cheese overlaps the edge of the toast by a 1/4" or so.
4. In a conventional oven turn the knob to "Broil" and place the cookie sheet with toast under the open flame or heating element about 8" - 10" from the heat. Close the door.
5. Here's the tricky part. And important. It takes a couple minutes to get the cheese melted, but the desired amount of "cooked" is past the stage of a grilled cheese sandwich. "Cooked" for us is an almost toasted-cheese level of cooking. The cheese will bubble on top. That's what you want to see. I let it get a good bubble working to where the oil is melting away from the cheese. BUT, if you let it go too far, all the oil and moisture will boil off and the cheese on toast will be tough, which my wife actually likes. I like it before it gets to that stage.
Make it better: In the summer, when tomatoes are fresh, I like to place a slice of tomato on top of the cheese after it has cooked a while and almost ready. When the tomato is warmed, in about a minute, it is ready.