1. FOR THE MEATLOAF: Adjust oven rack to middle position and heat oven to 350°F. Fold heavy-duty aluminum foil to form 9 x 5-inch rectangle. Center foil on wire rack set in rimmed baking sheet. Poke holes in foil with skewer (about 1/2 inch apart). Spray foil with vegetable oil spray.

2. Melt butter in 12-inch skillet over medium heat. Add onion and mushrooms; cook, stirring occasionally, until beginning to brown, 10 to 12 minutes. Add tomato paste and cook, stirring constantly, until browned, about 3 minutes. Reduce heat to low; add 3 tablespoons broth and garlic; cook, scraping bottom of pan to loosen any browned bits, until thickened, about 1 minute. Transfer mushroom mixture to large bowl to cool.

3. Whisk eggs, remaining 1/2 cup broth, and soy sauce together in bowl. Sprinkle gelatin over egg mixture and let sit until gelatin softens, about 5 minutes.

4. Pulse bread in food processor until finely ground, 5 to 10 pulses. Add gelatin mixture, cooled mushroom mixture, parsley, mustard, pepper, and thyme to bread crumbs and pulse until mushrooms are finely ground, about 10 pulses, scraping down bowl as needed. Transfer breadcrumb mixture to large bowl. Add pork and beef and mix with hands to thoroughly combine.

5. Transfer meat mixture to foil rectangle and shape into 9 x 5-inch loaf using wet hands. Bake meatloaf until it registers 155 to 160°F, 75 to 90 minutes. Remove from oven and turn on broiler.

6. FOR THE GLAZE: While meatloaf cooks, bring all ingredients to simmer in small saucepan over medium heat. Cook, stirring occasionally, until thick and syrupy, about 5 minutes.

7. Spread half of glaze evenly over cooked meatloaf; place under broiler and cook until glaze bubbles and begins to brown at edges, about 2 minutes. Remove meatloaf from oven and spread evenly with remaining glaze; return to broiler and cook until glaze is again bubbling and beginning to brown, about 2 minutes longer. Let meatloaf cool for 20 minutes before slicing and serving.

Serves 6 to 8