Heat oil in a large nonstick skillet over medium heat. Add garlic and crushed red pepper; cook, stirring constantly, until fragrant and the garlic is starting to turn golden, about 1 minute. Add the squash strands and toss to coat. Increase heat to medium-high and continue to cook, tossing often with tongs, until the strands are evenly coated and any liquid has evaporated, 2 to 3 minutes. Remove from heat and stir in lemon zest, pepper and salt. Transfer to a bowl and sprinkle with Parmesan. Garnish with more pepper, if desired.