Preheat the oven to 450°F. Wash and dry the fresh produce. Cut off and discard the ends of the squash. Halve lengthwise; using a spoon, scoop out and discard the pulp and seeds. Cut crosswise into 1/2-inch pieces. Cut off and discard the stem ends of the brussels sprouts; halve lengthwise. Halve and peel the onion(s); cut into 1/2-inch-wide wedges, keeping the layers intact. Core and small dice the pear(s). In a bowl, whisk together the mustard, honey, and 1/4 cup of water (or 1/2 cup for 4 servings); season with salt and pepper.

Line 1 sheet pan (or 2 sheet pans for 4 servings) with foil. Place the squash pieces, halved brussels sprouts, and onion wedges on the sheet pan(s). Drizzle with olive oil and season with salt, pepper, and the spice blend; toss to coat. Arrange in an even layer. Roast 18 to 22 minutes, or until browned and tender when pierced with a fork. Remove from the oven.

Meanwhile, pat the pork dry with paper towels; season with salt and pepper on both sides. In a medium nonstick pan (or large for 4 servings), heat a drizzle of olive oil on medium-high until hot. Add the seasoned pork. Cook 4 to 6 minutes per side for medium (the center may still be slightly pink), or until browned and cooked to your desired degree of doneness. Leaving any browned bits (or fond) in the pan, transfer to a cutting board and let rest at least 5 minutes. Slice the rested pork crosswise.

The USDA recommends a minimum safe cooking temperature of 145°F for pork.

To the pan of reserved fond, add the diced pear(s) and sauce (carefully, as the liquid may splatter). Cook on medium-high, stirring constantly and scraping up any fond, 2 to 3 minutes, or until slightly thickened. (For a thicker consistency, continue cooking the sauce. For a thinner consistency, add 1 tablespoon of water at a time to loosen.) Turn off the heat. Stir in the butter until melted and combined. Taste, then season with salt and pepper if desired. Serve the sliced pork with the roasted vegetables. Top the pork with the finished sauce. Enjoy!