This French Onion Pasta Bake takes your favorite French onion soup flavors and turns it into a delicious cheesy pasta dish. Caramelized onions, juicy chicken, flavorful sauce, with melty cheese over the top.
Two large yellow onions, peeled, halved, sliced into 1/8 inch half-moon slices
1 lb boneless skinless chicken breast, cut into 1 inch cubes
1 tsp Italian seasoning
3 tbsp unsalted butter
2 tbsp + 2 tbsp olive oil divided
3 tbsp + 2 cups beef stock divided
1 tbsp fresh thyme leaves (removed from stem)
1 small bottle pinot grigio (187ml)
1 tbsp all purpose flour
2 tsp better than bouillon beef paste
1 lb pasta shells, cooked al dente according to package instructions
Kosher salt and freshly ground black pepper to taste
1 cup freshly grated gruyere cheese
In a large cast iron skillet [see note] over medium heat, add the 2 tbsp olive oil and 3 tbsp butter. Once butter has melted, add in the onions and a pinch of kosher salt. Sauté the onions for 3-4 minutes until they begin to soften. Lower the heat to medium/low and continue to cook onions stirring frequently so they do not burn [see notes]. After 20 minutes, add in the 3 tbsp of beef stock and continue stirring the onions. For the rest of the caramelization process, you’ll need to be frequently stirring so the onions do not burn. The whole process of caramelizing the onions takes about 40-45 minutes [see notes for important tips].
While the onions are cooking, cook the pasta to al dente according to package instructions. Drain and set aside.
Remove the onions from the skillet using tongs and set aside. Turn the heat to medium/high, add in the 2 tbsp oil, the chicken, and the Italian seasoning. Cook chicken entirely through to 165 degree internal temperature. About 10 minutes. Remove the chicken from the pan and set aside.
Lower the heat to medium, return the onions back into the pan. Deglaze the pan with the white wine and allow the liquid to reduce by half. Once liquid has reduced, add the flour and stir until combined with the onions. Add in the fresh thyme, the 2 cups beef stock, the beef bouillon paste, and freshly ground black pepper. Stir until all combined. Add the chicken back into the skillet, allow the french onion sauce to come to a boil and lower the heat to simmer. Taste and adjust seasoning if necessary.
Turn the heat off, add in the pasta shells, and carefully mix the pasta into the french onion sauce. Top with the freshly grated gruyere cheese, and place in the oven. Low broil until the cheese has melted. Carefully remove from the oven, top with fresh thyme, and serve.
Use a large oven friendly skillet for the recipe since you’ll be transferring into the oven. Do not use smaller than a 10 inch high wall skillet, or whole dish will not fit. If you do not have an oven friendly skillet, transfer to a baking dish at step 5.
Caramelizing Onion Tips
Don’t slice your onions too thin, they will burn quickly if too thin. You want them to be about 1/8th of an inch.
Use a large skillet with high walls so onions aren’t over crowded and don’t fall out when stirring around. If the onions are too crowded, they will steam and take longer to caramelize.
Use a combination of butter and oil, just butter will burn with the long cooking process.
Start with the heat on medium to first soften the onions, then lower to medium/low. Do not turn the heat higher during the caramelization process.
Stir onions frequently so they do not burn. As the water evaporates from the onions, the onions may start to get stuck to the pan and get burnt. Add a few tbsp of beef stock to the onions.
After passing the 15/20 minute mark, you’ll need to be at the stove for the rest of the process stirring and ensuring they don’t burn. This is the point where most accidentally burn the onions so stay diligent!
Caramelized onions take about 45 minutes. They should be a rich brown color and the size reduced from when you started.
You can store caramelized onions in an air tight container for up to 1 week
Keywords: french onion, caramelized onions, french onion pasta, chicken