French Dip Panini with Au Jus

 
This is an upgrade on the Caramelized Onion and Gruyere Panini that I posted earlier this week. I've added thinly sliced deli roast beef and a hot Au Jus sauce for dipping. Voila! You have French Dip. The Au Jus presented a problem. The authentic homemade version comes from the drippings of cooking a roast. On a school night? Not happening. Nor did I want to buy a packet that you mix with water and is supposed to mimic the flavor of beef broth. Not natural; not for me. So here's what did work: shallot, garlic, and a box of natural/organic beef broth/stock slow simmered over the stove until reduced to 1/4 of it's original volume. Delicious concentrated beef flavor. Your hot panini will want to dive right in. My only warning is this: use low sodium stock unless you have a passion for salt.

INGREDIENTS
1 large onion per sandwich, thinly sliced
extra virgin olive oil
salt and pepper, to taste
Gruyere cheese, sliced
roast beef, thinly sliced
whole wheat bread
butter or cooking spray

Au Jus:
4 cups low-sodium beef stock/broth (1 box)
2 cloves garlic, minced
1 shallot, minced
dab of butter

DIRECTIONS
1. To caramelize the onions, heat several drizzles of olive oil in a large saute pan over medium heat. Add the onions and stir to coat with oil. Continue cooking over medium heat and stirring often until the onions are soft, deep brown, and caramelized. Season to taste with salt and pepper. The onions can be made ahead of time and refrigerated until ready to use.

2. To make the au jus, melt a dab of butter in a large saute pan over medium heat. Add the shallot and garlic and saute for several minutes. Add the beef broth, bring to a boil, then reduce heat to medium and simmer until reduced to about 1 cup. Season to taste with salt and pepper (boxed or canned broth is already very salty so you probably won't need to add salt). The au jus can be refrigerated until ready to use and reheated.

3. To assemble the panini, preheat panini press to high heat. Layer cheese, onions, and roast beef on slice of bread. Top with a second slice of bread. Spread butter on both sides of the sandwich or spray with cooking spray. Place on the preheated panini press and grill for several minutes until the outside is crispy and golden brown and the cheese has melted. Serve hot with warm au jus for dipping.

Makes about 1 cup of au jus.

(Adapted from Panini Happy)