Wash the zucchini and trim the ends.
To make zucchini noodles, use a spiralizer. If you do not have one, you can cut them by hand. Cut into long slices with a sharp knife and then use a peeler to slice from top to bottom to create the zoodles. You can also buy them already cut in most supermarkets.
Heat the oil in a saute pan over medium heat. Add the zucchini noodles and toss them for one minute, just to warm through, then turn off the heat.
In a large bowl, mash the avocado, onion, and cilantro with salt, pepper, and lemon juice.
Add the zoodles to the avocado mash and mix well.
Garnish with chopped cherry tomatoes and serve at room temperature.