Begin by heating 2 tablespoons of olive oil in a large skillet over medium-high heat until shimmering. Add the ground mild chicken Italian sausage, breaking it into small chunks with a spatula. Sauté for about 5-7 minutes until browned and cooked through. Remove from skillet and set aside.

In the same skillet, reduce heat to medium and add 2 tablespoons of unsalted butter to the drippings. Once melted, toss in finely diced shallots and pour in the balsamic vinegar. Cook for about 3-4 minutes until the shallots become golden brown.

Incorporate halved Brussels sprouts and diced sweet potatoes into the skillet, along with the remaining 2 tablespoons of butter, kosher salt, and black pepper. Sauté for 10-12 minutes until the Brussels sprouts are tender and slightly charred.

Return the browned sausage to the skillet, along with diced Honeycrisp apples and coarsely chopped pecans. Cook for an additional 3-5 minutes until everything is heated through.

If desired, sprinkle finely grated Parmesan cheese on top just before serving. Serve the dish in bowls.