Saute the onions in hot oil in a skillet until softened. Set aside.
Process the chickpeas and cooked potatoes in a food processor using the metal “S” blade.
Place the ground chickpeas, potatoes and remaining ingredients in a large mixing bowl; mix well.
Using your hands, knead the ingredients together, making sure the mixture holds together. NOTE: keep a bowl of water nearby to dip your hands, if mixture feels a little dry.
Shape the mixture into 21 ping pong sized balls.
Cut 21 (6”x6”) squares out of two-ply cheesecloth, and 21 (10”) strands of kitchen twine.
Wrap each ball in a cheesecloth and tie the top with a piece of twine.
Cook several topiks at a time in a pot of salted, gently boiling water, until they float to the top- about 5 to 7 minutes.
Remove each from water; allow them to cool on a wire rack; untie them.
Serve the topik with a drizzle olive oil and squeeze of fresh lemon.