Preheat the broiler. To prepare crostini, arrange baguette slices on a baking sheet in a single layer. Broil, turning, until golden brown, about 2 minutes. Transfer to a wire rack to cool.
Rub crostini with tomato. Drizzle with olive oil. Top each crostini with a slice of ham. Brush with olive oil. Arrange on a serving platter and sprinkle with parsley.