Start by preheating your oven to 375°F. While it heats, prepare all your ingredients: mince the garlic, dice the onion into 1/4-inch pieces, seed and mince the jalapeño (I remove the seeds for a milder heat, but leave them if you like more spice), shred both the Gouda and white cheddar cheeses, and cut or shred the rotisserie chicken into bite-sized pieces. Drain and rinse the great Northern beans. Having everything prepped and ready will keep the cooking process smooth and prevent any scrambling once you start building the sauce.

Bring a large pot of salted water to a boil and add the pasta shells. Cook for 8 to 10 minutes until just al dente (it should have a slight firmness when bitten). Drain the pasta and set it aside—don't rinse it, as the starch will help the final dish cling together nicely.

Heat the olive oil in a large skillet over medium heat. Add the diced onion and minced jalapeño, then season with 1/2 teaspoon of salt. Cook for about 7 minutes, stirring occasionally, until the onion is softened and translucent. Add the minced garlic, smoked paprika, and ground cumin, cooking for just 1 minute more until fragrant. This layering of aromatics and spices creates the foundational flavor for the entire dish.

Add the butter to the skillet and stir until completely melted and combined with the aromatics. Sprinkle the flour over the mixture and cook for 1 to 2 minutes, stirring constantly, to create a roux that will thicken the sauce. Gradually whisk in the chicken broth and heavy cream, stirring continuously to avoid lumps. Simmer for 1 to 2 minutes until the sauce thickens enough to coat the back of a spoon. I find that using good-quality butter like Kerrygold really elevates the richness here.

Reduce the heat to medium-low. Add 1.5 cups of Gouda and 1.5 cups of white cheddar cheese to the sauce, stirring constantly until both cheeses are completely melted and the sauce is smooth and creamy. Taste the sauce and adjust the seasoning with additional salt and black pepper as needed. This two-cheese blend creates a complex, rich flavor that defines the dish.

Add the shredded chicken, drained beans, frozen corn, and cooked pasta from Step 2 to the cheese sauce. Fold everything together gently but thoroughly, ensuring the pasta and other ingredients are evenly coated. Transfer the entire mixture to a 9x13 inch baking dish (or similar size). Sprinkle the remaining 1/2 cup of Gouda and 1/2 cup of white cheddar evenly over the top. This top layer of cheese will create a gorgeous golden crust as it bakes.

Bake the chili mac in the preheated 375°F oven for 25 to 30 minutes until the top is golden brown and the sauce is bubbling around the edges. Remove from the oven and let it rest for 2 to 3 minutes before serving. Top with the chopped fresh cilantro just before serving for a bright, fresh contrast to the rich, creamy dish.