Finely chop the onion.

Pour boiling water over lettuce leaves to soften them.

In a bowl, mix ground pork, chopped onion, breadcrumbs, milk, and a pinch of salt and pepper.

Lay out a lettuce leaf, place the meat mixture near the stem side, and add a cherry tomato in the center of the meat.

Wrap the meat mixture and tomato with the lettuce, folding the sides inward and rolling tightly.

Place the rolls seam-side down in a pot, add the soup base ingredients, and heat over medium heat.