How to Make It
Lightly oil a 9-by-13-inch baking pan. Heat the olive oil in a large saucepan. Add the onion, garlic and rosemary and cook over moderate heat until the onion is very tender, 6 minutes. Stir in the sambal oelek. Add the water and bring to a boil. Slowly whisk in the chickpea flour until smooth. Reduce the heat to low and whisk until very thick, about 6 minutes. Season with salt. Spread evenly in the oiled baking pan and press plastic wrap on the surface. Refrigerate until firm, at least 4 hours.
In a large pot, heat 2 inches of oil to 350°. Cut the chickpea mixture into 4-by-3/4-inch fries and pat dry with paper towels. Lightly dust the fries with flour. Fry in batches until golden, 8 minutes. Drain on paper towels, season with salt and serve.