Cook beans in salted water until tender. Drain and transfer to cold water. Cut shallots lengthwise in half and remove peel. Melt butter and oil in skillet over medium-high heat. Add shallots and sauté for 1 minute. Reduce heat to medium-low. When shallots are browned and tender, season with thyme, salt, and pepper. Mix beans and shallots together; heat and serve.