This is like a cross between a Philly Cheese and a French Dip. It could be made better with the addition of a thin layer of horseradish spread on the matzo brie before adding the onions, meat and cheese. Also, sauteed mushrooms would be a great addition.
And of course, this is only kosher for Passover if you a) are willing to eat moistened matzo, which some people avoid, and b) you either don't keep kosher otherwise (I only observe Passover for the tradition, not for the religious aspect, really) or you forgo the cheese, since meat and dairy together is a no-no.
2 matzo crackers, broken in to small pieces
1 large egg
Salt and pepper to taste
2 tablespoons butter or margarine, for frying
3 tablespoons yeast-free beef broth (season with salt and onion powder as needed)
1/4 lb rare deli roast beef
3 slices provolone (optional)
A bit of butter for frying
1/4 cup thinly sliced onion
1 tablespoon cola
Over a colander, in the sink, break matzo into small pieces.
Run water over matzo for a minute or two to soften, tossing with your hands to ensure it all gets moistened.
It should be softened but not mushy enough that it no longer holds its shape.
In a medium frying pan, melt butter over medium heat.
While the butter melts, beat one egg in a medium sized bowl, season with salt and pepper.
Add broken moistened matzo to beaten egg and mix well.
Transfer matzo mixture into the pan, pat down into a pancake like form and fry until golden brown, then turn and brown the other side.
While the matzo brie is in the pan, in a small fry pan, over medium heat, melt butter and saute the onion until translucent. Add the cola, allowing the onions to caramelize, while tossing them lightly.
In a small sauce pan, heat the beef broth until near boiling and add the roast beef to warm, about one minute.
Preheat your broiler, as needed.
Assemble the open-faced sandwich on a baking sheet, lined with foil. Place the finished matzo brie pancake on the sheet pan, top with onions, evenly distributed, then the roast beef, and cover with cheese. Place under the broiler and allow the cheese to melt, transfer to a plate if you can wait that long, then eat hot.
Serves 1-2 (depending upon appetite)