Finely chop onion. Set aside in small bowl.
Finely mince garlic or press through garlic press. Set aside in small bowl.
Remove lobster meat from lobster tail. Cut lobster into bite size pieces and set aside in small bowl. Use kitchen shears or sharp knife to cut lobster shells into small pieces (approx. 1 inch). You want the pieces to be smaller to allow them to be more submerged in the cooking liquid.
In large sauté pan, heat oil and butter over medium heat. When oil and butter are hot (about 1-2 minutes), add red onion and thyme.
Sauté until red onion is soft (about 2-3 minutes). Add garlic, sauté about 1 minute.
Add chopped lobster and cook fully (about 1-2 minutes). Remove cooked lobster and set aside on plate.
Add lobster shells and sauté for 1-2 minutes. You can add an additional 1-2 tablespoons of butter or oil if needed.
Add brandy and allow alcohol to cook off. It should be hot and sizzling when you add it. Cook for another 1-2 minutes.
Slowly pour in heavy cream, stirring as you pour. Once cream comes to a boil, drop to medium and simmer.
Add old bay seasoning. Simmer until sauce is slightly thickened.
Once you can taste your lobster flavor, carefully strain out lobster shells using a fine mesh strainer and large bowl.
Add strained sauce back into sauté pan on medium heat, continue to reduce sauce until it reaches desired thickness. Add salt and/or fresh ground black pepper to your taste.
Add your lobster back to sauce to warm. Gently stir in your ravioli to warm. Or, allow sauce to reduce to desired thickness and spoon over plated lobster ravioli.
Note: If you add the ravioli directly to the sauce, the starch will help to thicken the sauce. If you wish to spoon the sauce, you can continue to reduce the sauce on medium/low heat or you can add a small amount of cornstarch or flour to thicken (start with 1 tsp). It depends on how thick you enjoy your sauce.