In 4-quart Dutch oven, melt butter with oil over medium-high heat. Add garlic and shallot; cook 2 minutes, stirring constantly, until shallot is tender. Add tomato paste; cook 1 minute, stirring constantly. Stir in roasted peppers and broth; heat to boiling. Reduce heat to medium; simmer uncovered 5 minutes, stirring occasionally. Remove from heat; cool 10 minutes.