Slice the loaf of bread into approximately 1-inch thick rectangles or rounds, making about 20 pieces. Arrange the slices on a baking sheet.
Toast the bread slices in a preheated oven at 180°C (350°F) for 5-8 minutes, until the edges turn golden brown and the slices are slightly crispy.
While the bread is toasting, prepare the fillings by slicing the deli meats into small strips, slicing the cheese, halving the cherry tomatoes, and tearing the lettuce into manageable pieces.
Remove the toasted bread from the oven and let it cool for a minute or two—this helps the fillings stick better.
Spread a thin layer of mayonnaise or mustard on each bread slice using the back of a teaspoon for even coverage.
Layer a few slices of deli meat, a piece of cheese, some cherry tomato halves, and a leaf or small pile of lettuce on top of each slice.
Gently press down each assembled mini sandwich to help the layers stay in place.
Arrange the mini sandwiches on a serving platter. Optionally, you can add a sprinkle of salt and pepper for extra flavor.
Serve immediately for the best crunch, or refrigerate loosely covered for up to 2 hours if preparing ahead.
