French Onion Sliders

To make the caramelized onions, combine the butter and 1 tablespoon olive oil in a large skillet over medium heat. When the butter melts, add the sliced onions to the skillet with the salt, pepper, and sugar. Stir well to combine, then reduce the heat to medium-low. Cook, stirring occasionally, until onions are golden brown and fully caramelized, about 15 to 20 minutes. Stir in the thyme and cook until fragrant, about 1 minute. Increase the heat to medium-high. Remove skillet from heat; add wine. Return to stove and continue to cook over medium-high heat, stirring frequently, until most of the liquid has cooked off. Remove from the heat and set aside.

Rub one side of each baguette slice with the cut side of a garlic clove. Layer 12 baguette slices with a bit of the sliced Gruyere, 2 to 3 teaspoons of the caramelized onion mixture, and another slice or two of cheese. Place the remaining baguette slices on top. Lightly brush the tops with some of the remaining olive oil. Bake in a 400° oven for 15 minutes, flipping once and brushing with remaining olive oil halfway through baking. Serve warm.