Arrange all the greens on a tray.
In a bowl place ground pork, five spice powder, salt, fish sauce, shallots, garlic, and pepper. Marinate for about one hour, and then form small, 1" meatballs. Flatten them out to form a patty.
While the pork is marinating, slice the kohlrabi thinly, and place in a shallow glass dish. Each slice of kohlrabi should be cut into 3 wedge shaped pieces. Sprinkle with kosher salt and vinegar, and allow it to sit for about 1 hour.
Cook meatballs/patties in a skillet, on both sides. When finished, transfer them to a baking tray and place them in the oven on broil for about two minutes on each side. (If you want to grill outdoors: Grill them from about 3 minutes per side until they run clear and hit an internal temp 145° F.)
Prepare the broth by placing fish sauce, water, lime juice, brown sugar and rice vinegar in a small sauce pan. Bring to a boil, and remove from heat.
Divide the broth evenly into 4 separate bowls.
Place the sliced kohlrabi in the broth. You typically eat them by alternating dipping the meatballs, greens and noodles into the broth. It is very refreshing!