Preheat oven to 400.
Spread out mushroom caps on a baking sheet and brush them with 1 Tbsp. of olive oil.
Once oven is heated cook mushroom caps for 7 minutes.
While mushrooms cook, add 2 tbsp of olive oil and then add garlic and onions. Cook until onions are translucent.
Add Italian sausage and begin to brown. Then add white bottoms of the green onions.
Add garlic salt and onion powder.
Once the meat is cooked, turn the heat off and add the fresh basil. Stir.
Next add cheeses one-by-one. Continually stir so the cheese doesn't burn.
Once all the cheese has been added remove the pan from the heat and mix well.
Add sausage mixture to mushroom caps and top with a little bit of extra cheese.
Cook in the oven for 5 -10 minutes. Continue to check to mushrooms so they don't burn but make sure they are soft before you remove them.
When done, top the Sausage Stuffed Mushrooms with fresh thyme and serve!