Using a spiraliser, create zucchini spaghetti (always read the directions as they vary by brand). If you don't have a spiraliser use a regular vegetable peeler to vertically peel long, thin strips of the zucchini. This will form more of a wider "noodle" from the zucchini, like fettuccini.
Heat one tablespoon of olive oil in a large frying pan over medium-high heat. Once hot, add zucchini noodles and cook for about 90 seconds, until zucchini noodles are tender but still retain some crunch. Super important - don't overcook!
Transfer into a colander and let the noodles rest for about 3 minutes so that they can release all of the moisture.
Wipe the pan and heat one tablespoon of olive oil, when sizzling add chicken cubes and cook until browned on all sides.
Add tomatoes and parsley, lower to a simmer and cook for 3-5 minutes, or until tomatoes start to break down and release some of their juice.
In a small bowl combine lemon juice, the remaining tablespoon of olive oil, garlic, salt, and pepper.
Add the lemon juice mixture and stir until combined. Cook for 1 minute.
Plate up the zoodles then add the chicken mixture on top. Sprinkle with Parmesan cheese and red pepper flakes (optional). Serve immediately.