Place dried mushrooms into a small bowl, and cover with hot water; soak 10 minutes. Remove with a slotted spoon, and gently squeeze dry with paper towels. Chop mushrooms, and set aside.
Scoop cream of mushroom soup into a bowl, and gradually stir in boiling water until mixture is smooth but not runny.
In a saucepan over medium heat, bring the stock to a gentle simmer.
Heat butter and olive oil in a large pot over medium heat. Stir in onion, garlic, and chopped mushrooms; cook about 3 minutes. Gradually stir in rice; cook 2 minutes, stirring constantly to coat rice with oil. Season with salt and pepper. Stir in thyme and basil to taste.
Pour in the mushroom soup mixture, stirring until absorbed. Gradually add 1/3 stock, stirring until liquid is absorbed. Continue to stir in stock gradually, 1 cup at a time, allowing the liquid to be absorbed before adding another cup. It should take about 20 minutes for all the stock to be absorbed and the rice becomes al dente (tender but firm to the bite).