Preheat oven to 400°F.
While oven is preheating, cook bacon according to package directions until firm but pliable and not crispy. Remove bacon and set aside.
Reserve 1 tablespoon bacon drippings in same skillet used to cook bacon and sauté mushrooms over medium heat for 6-10 minutes until golden brown in color. Set aside to cool.
Spray muffin tin with non-stick cooking spray. Cut six strips of cooked bacon into quarters. Place one full strip of cooked bacon around the side and two quarters of a strip in the base of each of six muffin cups in a muffin tin. Use your fingers to press overlapping ends of bacon together.
In large bowl, beat 4 eggs and whisk in mushrooms, chopped thyme and black pepper.
Pour egg mixture in equal portions into muffin cups lined with bacon, about 2/3 full in each cup.
Sprinkle equal portions of shredded cheese into the cups and top each with two quarter strips of bacon.
Place filled muffin tin in oven and bake for 20 minutes, or until egg is completely set, cheese is melted and tops are browned.
Remove muffin tin from oven, use knife to loosen edges, serve and enjoy!