Add olive oil and mushrooms to saute pan and cook for about 5 minutes.
Add shallot and garlic to the pan and cook for another 3 minutes.
Stir in flour and cook for 1 minute.
Add in rest of the ingredients and bring sauce to a simmer.
Reduce heat and continue cooking (and stirring) until the gravy reaches your desired consistency (3-5 minutes). Feel free to add more herbs/spices/salt to your liking.
*This recipe makes about 2 cups of gravy.