1Heat oven to 350°F. In 3-quart saucepan, place Brussels sprouts; add enough water just to cover. Heat to boiling; boil 6 to 8 minutes or until crisp-tender. Drain and return to saucepan; set aside.
2Meanwhile, in 10-inch skillet, cook bacon over medium heat, stirring occasionally, until crisp. Remove bacon with slotted spoon; drain on paper towels and set aside. Drain all but 1 tablespoon bacon fat from skillet.
3Add butter to bacon fat in skillet. Heat over medium-high heat until butter is melted. Add onion; cook 2 to 3 minutes, stirring frequently, until crisp-tender. Add flour, thyme and pepper; cook and stir until well blended. Gradually stir in half-and-half and bouillon granules. Heat to boiling, stirring constantly; boil and stir 1 minute. Remove from heat; stir in Parmesan cheese.
4Pour sauce over Brussels sprouts in saucepan; mix gently. Spoon into 2-quart casserole. Bake uncovered 25 to 30 minutes, sprinkling with crumbled bacon and Cheddar cheese for last 10 minutes of baking, until hot and bubbly.