Slow Cooker Marinara Chicken Subs Recipe -

Transform ordinary weeknights or game-day gatherings into an absolute feast with these comforting, melt-in-your-mouth marinara chicken subs.

Tender, juicy chicken breasts simmer slowly in a rich, herbed tomato sauce until they easily fall apart. Piled high into golden, buttered sub rolls and blanketed under a double layer of gooey, bubbling cheese, this dish delivers maximum flavor with minimal effort.

Recipe Overview

Prep Time: 10 minutes
Cook Time: 4 hours
Total Time: 4 hours 10 minutes
Servings: 8

Ingredients

3 pounds boneless, skinless chicken breasts
1 1/2 jars (48 ounces total) your favorite marinara sauce
2 teaspoons onion powder
1 tablespoon Italian seasoning
2 tablespoons minced garlic
1 teaspoon salt
1 teaspoon freshly ground black pepper
3/4 cup freshly grated Parmesan cheese (plus extra for garnish)
1 cup shredded mozzarella cheese
8 slices provolone cheese
8 fresh sub rolls
4 tablespoons unsalted butter, melted
Chopped fresh parsley, for garnish

Step-by-Step Instructions

1. Simmer the Chicken

Place the boneless, skinless chicken breasts into the bowl of a slow cooker. Pour the marinara sauce evenly over the top, ensuring the meat is well coated. Sprinkle in the onion powder, Italian seasoning, minced garlic, salt, and black pepper.

Cover the slow cooker with its lid and cook on Low for 4 to 6 hours (or on High for 2 to 3 hours) until the chicken is exceptionally tender and cooks through completely.

2. Shred and Enrich

Once cooked, turn off the slow cooker and carefully transfer the hot chicken breasts to a clean cutting board. Using two forks—or a hand mixer on low speed for a quick shortcut—shred the meat into bite-sized pieces.

Return the shredded chicken back into the rich marinara sauce inside the slow cooker and stir thoroughly. Fold in the 3/4 cup of grated Parmesan cheese until fully incorporated and creamy.

3. Toast the Sub Rolls

Preheat your oven to 400°F (200°C). Slice the sub rolls open lengthwise, taking care not to cut all the way through. Brush the interior of each roll generously with the melted butter.

Arrange the rolls on a baking sheet and toast them in the preheated oven for a few minutes until the edges turn golden brown and crisp.

4. Assemble and Melt

Remove the toasted rolls from the oven. Layer a small handful of shredded mozzarella cheese along the inside bottom of each bun.

Generously spoon the hot, cheesy marinara chicken mixture directly over the mozzarella. Lay a slice of provolone cheese flat across the top of the chicken filling.

5. Final Bake and Garnish

Return the assembled sub sandwiches on the baking sheet back to the oven for 3 to 4 minutes, or until the provolone and mozzarella cheeses are completely melted, bubbly, and slightly golden.

Remove from the oven, garnish with fresh chopped parsley and an extra sprinkle of grated Parmesan cheese, and serve immediately while hot.

Chef’s Cooking Tips

Shredding Shortcut

Using a hand mixer on low speed inside a deep bowl or right in the slow cooker insert cuts shredding time down to less than 30 seconds.

Preventing Soggy Bread

To keep your sub rolls structurally sound, make sure to drain excess liquid from the chicken mixture with a slotted spoon as you pile it onto the bread, or toast the bread slightly longer so it forms a moisture barrier.

Make-Ahead Friendly

The marinara chicken mixture can be made up to two days in advance and kept in the refrigerator. Just reheat it on the stove or in the slow cooker before assembling the subs.

Nutrition Facts (Per Serving)

Nutrient	Amount	% Daily Value
Calories	694	—
Total Fat	29g	37%
Saturated Fat	14g	69%
Cholesterol	198mg	66%
Sodium	1955mg	85%
Total Carbohydrate	34g	12%
Dietary Fiber	5g	18%
Total Sugars	11g	—
Protein	71g	142%
Calcium	517mg	40%
Iron	5mg	27%
Potassium	1203mg	26%
Vitamin C	6mg	6%