The crispiness (really a great contrast to the meatballs) and coolness of the cucumber really makes these sliders stand out in the crowd. As does the tomato. They’re quite yummy and addicting.
Place meatballs and sauce in a large sauce pan or pot and warm over medium heat.
Place a slice (or two if they are small) of cucumber on each slider roll bottom.
Add a meatball with a little of the sauce. Note: I flattened the meatballs just slightly using a wooden spatula so they would look a little larger on the buns. If you're using larger meatballs you can probably skip flattening them.