Preheat oven to 350 degrees and lightly grease the baking dish(s) you are planning to cook your meatloaf in.
Pulse onions and mushrooms in a food processor until fine and evenly blended.
Heat sautée pan over medium-high heat and add oil. Add mushroom mixture and cook, stirring often, until all liquid has evaporated. Add garlic and thyme and stir one more minute. Add red wine and cook until liquid again has evaporated. Season to taste and set aside to cool.
Stir bread crumbs and crushed tomatoes in a small bowl and set aside. In a large bowl blend beef, pork and sausage with eggs, salt and pepper. Add tomato soaked bread crumbs to meat and stir in, then blend in mushroom mixture.
Spoon meatloaf filling into prepared tins or casserole dishes and bake covered for 30 minutes, remove cover and bake an additional 10 minutes uncovered until an internal temperature of 170 degrees is reached.
Alternatively meatloaf recipe can be prepared in a 8" inch loaf pan and baked for about an hour in total, covered for 45 minutes and uncovered for the remaining 15 minutes