INGREDIENTS
2 tbsp
olive oil
8 tbsp
butter
4 larges
portobello mushroom caps
1/8 tsp
salt
1/8 tsp
pepper
3 tbsp
mayonnaise
3 tbsp
parmesan cheese
1/8 tsp
onion powder
8 slices
sourdough bread
4 oz
brie cheese
1/2 cup
sharp cheddar cheese
1/2 cup
monterey jack cheese
1/2 cup
gruyere cheese
2 tsp
fresh thyme