For Meatloaf: Sauté onions and peppers in hot oil in medium skillet on medium-high heat until translucent. Add garlic. Cook 30 seconds. Remove from heat; cool.
Lightly mix sautéed vegetables, meat, barbecue sauce, cracker crumbs, eggs and spices in large bowl. Press into 9x5-inch loaf pan.
Cook in 200°F smoker 2 hours. Increase temperature to 325°F. Cook 1-1/2 hours or until internal temperature reaches165°F. Cool completely in pan, then refrigerate. When ready to use, remove meatloaf from pan; cut into 10 slices.
For Roasted Plum Tomatoes: Cut each tomato lengthwise into 3 slices. Place slices on parchment paper-lined sheet pan. Drizzle with olive oil; sprinkle with salt and pepper.
Bake in 300°F standard oven 40 to 45 min. or until partially dried but still moist. Cool in pan on wire rack.
For Each Sandwich: Wrap 1 slice Meatloaf with 2 slices bacon. Cook in skillet or on flat-top grill until bacon is crisp and meatloaf is heated through.
Spread 1 Tbsp. mayonnaise on bottom half of 1 roll. Top with 2 roasted tomato slices, meatloaf slice and 1/4 cup microgreens. Cover with top of roll.