Combine the water, dried mushrooms, and garlic in your Instant Pot. Close and SEAL. Pressure cook on high for 10 minutes. Carefully quick release, gently shake or tap the pressure cooker, and THEN carefully open away from you. Season with the salt pepper, and thyme. Wait a minute or two, stir, and taste. If it tastes flat to you, add more salt and pepper, until it tastes delicious. Freeze any broth you aren't going to use within a few days.