Bring a large pot of salted water to a boil. Add the wide egg noodles and cook until al dente, about 7 minutes. Drain and set aside for later use.

In a large skillet, melt the unsalted butter over medium heat. Add the finely chopped onion and cook until translucent, about 4-5 minutes. Stir in the minced garlic and cook for an additional 30 seconds for a fragrant base.

Stir in the all-purpose flour and cook for 1-2 minutes to form a roux, which will thicken your filling.

Slowly whisk in the chicken broth and then pour in the milk. Stir constantly until the sauce thickens, about 4-5 minutes.

Season your sauce with salt, black pepper, dried thyme, and paprika.

Add the shredded chicken, thawed mixed vegetables, and cooked noodles to the skillet. Gently stir to combine everything evenly.

Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish and transfer the chicken mixture into it, spreading it evenly.

Open the can of refrigerated biscuit dough and place the biscuits on top of the casserole, spacing them slightly apart for even cooking.

Bake uncovered in the preheated oven for 20-25 minutes, or until the biscuits are golden brown and fully cooked.

Allow the casserole to rest for 5 minutes after removing from the oven. Garnish with fresh parsley before serving warm.