Cut the zucchini into fries and or ribbons.: When you slice the zucchini , notice the contrast between the pale interior and the darker skin, and feel the firm but yielding flesh under your knife. Shoestrings should be thin and uniform so they crisp quickly, while ribbons need a steady hand and a vegetable peeler to create long, silky strips that wilt slightly when fried. A common mistake is cutting uneven pieces, which leads to some being overcooked and others undercooked, so aim for consistent thickness. If you hear a dull thud when slicing, your blade might be dull, which increases tear and uneven shapes. Keep pieces similar in size for even frying.
Heat the oil in large pot so that its at least 1/4 full and bring it to 190 C.: As the vegetable oil warms, it will change from glossy to slightly more fluid and shimmer when it approaches frying temperature. At 190 C the oil should produce a steady sizzle when a sliver of zucchini is gently touched to it. Use a thermometer if you can, since oil that is too cool will make greasy, soggy fries, while oil that is too hot will brown them too quickly. One trap is adding too much at once which drops the oil temperature; fry in small batches to keep heat steady. If your oil smokes, reduce the heat and let it cool to the proper range before continuing.
Gently dredge the zucchini in the milk and then toss them around the seasoned flour until well coated.: When you dip the zucchini into cold milk , you’ll notice the surface becomes slightly tacky, which helps the seasoned flour adhere. Tossing should feel light and even so the flour forms a thin wrap rather than a heavy batter. The flour will move from powder to a fine crust on the zucchini, and the smell is subtle, mostly of raw flour with a hint of seasoning. Avoid clumping by shaking off excess flour; clumps lead to dense, doughy spots when fried. If the coating falls off in the oil, it usually means the zucchini was too wet or the flour was applied too heavily.
Drop them in the hot oil in batches and fry for around 3 minutes and until they turn a golden brown.: As each piece hits the oil, listen for a lively sizzle that calms into a steady hiss, and watch color transform from pale to a warm golden brown. The sound is a reliable guide; a faint sizzle means the oil is cooling, a loud roar means it might be too hot. Frying for about 3 minutes usually gives crisp exteriors and tender interiors for thin cuts, but thickness matters so watch for visual cues over clock time. A common error is overcrowding, which causes the temperature to plummet and yields soggy fries, so maintain generous spacing as they float and dance in the oil.
Lift out with a slotted spoon or mesh strainer and drain on kitchen paper and serve.: When you remove the fries, they should glisten lightly with oil and sound crisp when tapped. Draining on paper absorbs excess oil so the coating stays crunchy, and a gentle sprinkle of salt at this stage sticks to the warm surface and brightens every bite. Pay attention to residual heat; leftovers will continue to crisp briefly, but prolonged sitting under a lid will steam them. One mistake is stacking fries while hot, which traps steam and makes them limp, so arrange them in a single layer until ready to serve.