- 4 slices dense, crusty bread like sourdough
- 1 Tbsp olive oil
- 4 Tbsp dijon mustard
- 8–12 slices deli roast beef
- 1–1 1/2 cups caramelized onions
- 1/2 tsp fresh thyme
- 4–8 slices swiss cheese
- Preheat oven to 450°F or the broil setting.
- Line a sheet pan with the 4 slices of bread and brush lightly with oil.*
- Broil on the top rack for a minute or less, just to dry out and crisp up the bread.
- Let cool slightly before topping each with a Tbsp of the mustard, then roast beef and caramelized onions.
- Sprinkle the thyme over all 4 and top with swiss cheese.
- Place back on the top rack of the oven and broil 2-4 minutes longer, just enough to melt the cheese.
- Remove and serve warm.
- sheet pan
- pastry brush or oil sprayer
The range of measurements depend on the size of your bread. For large slices, use the larger measurement.
- Prep Time: 5 minutes
- Cook Time: 10 minutes
- Category: Main Dish
- Method: Oven
- Serving Size: 1
Keywords: roast beef and caramelized onion toast, open faced sandwich with roast beef and onions