Fry the bacon strips in a shallow pan over medium heat until crispy on both sides, about 4 minutes per side; remove and drain on paper towels, leaving the bacon fat in the pan.
Finely chop the 2 onions and fry in the bacon fat over medium heat for 6 minutes until translucent.
Squeeze the soaked roll until almost all liquid escapes.
Put the minced meat in a large bowl and add the squeezed roll, egg, cooked onions, 4 tablespoons BBQ sauce, 3 tablespoons mustard, and 4 drops smoked oil.
Crumble the cooled bacon and add to the mixture along with paprika powder, salt, and pepper.
Knead the mixture vigorously until combined; add breadcrumbs if needed to reach a firm, moldable consistency.
Form meatballs weighing roughly 50 grams each.
Fry the meatballs in the bacon fat over low heat for 5 minutes on each side, being careful not to brown the breadcrumbs.
Toast the bread slices and serve the meatballs on top with BBQ sauce.