In a large skillet over medium heat, add olive oil and sauté the chopped onions for 3-4 minutes.
Stir in the minced garlic and sauté for another 1-2 minutes.
Fold in the chopped mushrooms and cook for 5-7 minutes until dry.
Remove from heat and let the mushroom mixture cool slightly.
In a mixing bowl, combine cream cheese, sour cream, and mayonnaise until smooth.
Add shredded mozzarella, grated Parmesan, thyme, and red pepper flakes, seasoning with salt and pepper.
Gently fold in the cooled mushroom mixture.
Transfer the dip mix to a baking dish.
Bake for 25-30 minutes until golden and bubbly.
Cool for a few minutes, then garnish with parsley.
Serve warm with baguette slices or tortilla chips.
Notes
Ensure mushrooms and garlic are finely chopped for even cooking. Let the mushroom mixture cool before combining to avoid melting the cream cheese too quickly.