Clean the chicken livers: Trim off any green spots, membranes, and stringy white connective tissue. Rinse briefly under cold water, then pat dry gently with paper towels.
Place a wide skillet over medium-high heat. Add 2 tablespoons of oil and the onion, season with salt, and fry for 7–10 minutes, until golden brown. Transfer the onions to a bowl and set aside.
Add the remaining oil to the skillet and sear the chicken livers on both sides, about 2 minutes per side, until fully cooked. Season with salt and pepper. Transfer the livers to a sieve set over a wide bowl and allow them to cool completely, then discard the liquid.
Transfer the chicken livers and onions to a large cutting board and chop them together until paste-like. Add the harissa and continue to chop and mix until fully incorporated. Taste and adjust the seasoning with more salt, pepper, or harissa as needed.
Transfer the mixture to a piping bag and cut a ½-inch opening at the tip.
In a small bowl, mix together the flour and water to make a paste. This will act as the glue to help the wrappers stay sealed.
To assemble, cut each sheet of brik dough in half to form two equal semicircles. If using lumpia wrappers, keep the unused ones covered with a damp towel to prevent them from drying out (brik wrappers do not require this step). Place one semicircle with the straight edge facing you and brush the round edges with a thin layer of the flour mixture. Pipe the filling along the bottom edge in a 6-inch-long, ½-inch-wide line. Fold the sides over the filling, then roll into a cigar shape. Repeat with the remaining filling and brik dough. Check out this GIF to see the rolling technique.
Pour ½ inch of oil into a heavy-bottomed sauté pan over medium-high heat. When it’s shimmering, but not yet smoking, add a few cigars to the pan and fry for 2–3 minutes per side, turning halfway through, until golden brown on all sides. Transfer the cigars to a paper towel-lined plate or wire rack, and fry the remaining cigars in batches.
Serve immediately with tahini sauce.
Fully rolled cigars can be frozen for up to 2 months and fried directly from frozen.
