How to Make It
In a small saucepan, heat the oil until shimmering. Add the garlic, tomato paste and sambal oelek and cook over moderately high heat, stirring, until the garlic is golden brown, about 30 seconds. Stir in the stock, hoisin sauce, peanut butter and sugar and bring to a boil. Simmer over moderately low heat until reduced slightly, about 3 minutes. Let cool completely, then stir in the ground peanuts. Transfer to a serving bowl and scatter the sliced chile on top.
In a large colander set over a bowl, toss the shrimp with 1 tablespoon of salt. Cover and refrigerate for 1 hour. Rinse well and pat dry. Transfer the shrimp to a food processor.
Bring a small saucepan of water to a boil. Add the fatback and boil until softened slightly, about 10 minutes. Drain well, then add the fatback to the processor along with the shallots, garlic and sugar and pulse until very finely ground. Add the fish sauce, rice powder and black pepper and puree until smooth. Add the ground chicken and pulse until fully incorporated.
Lightly oil a baking sheet. With lightly oiled hands, press 2 tablespoons of the shrimp mixture in an oval shape around each sugarcane skewer, leaving 2 inches of the skewer exposed to act as a handle. Arrange on the oiled baking sheet.
Light a grill or preheat a grill pan and brush with oil. Working in batches if necessary, grill the skewers over moderate heat, turning occasionally, until white throughout, about 8 minutes.
To serve, place a few strips of carrot and cucumber in each lettuce leaf and top with a skewer, a spoonful of the dipping sauce and a sprinkling of ground peanuts and mint and cilantro leaves.
The dipping sauce can be refrigerated for up to 5 days. The uncooked skewers can be refrigerated overnight.
Roasted rice powder, known as khao kua pon in Thailand, is popular in East Asian cooking for its toasty flavor and its binding effect. It’s available at Asian markets. Or, you can make it: In a small skillet, toast raw glutinous (sticky) rice over moderately high heat, stirring occasionally, until golden brown and fragrant, 3 to 4 minutes. Transfer the rice to a mortar or spice grinder and let cool completely. Grind the rice to a coarse powder. Sugarcane swizzle sticks are available in the fruit department of many large supermarkets or through melissas.com. Alternatively, look for canned sugarcane in syrup at Asian markets; you’ll have to drain the sugarcane and cut it into lengthwise sticks with a sharp knife.