Place the olive oil in a large saute pan over medium-low heat.
When hot, add the diced onion with a pinch of salt.
Cook for 15 minutes, stirring as needed, until caramelized.
Add the garlic, zucchini, and corn with a large pinch of salt and cracked pepper and cook for a mere three minutes, stirring once.
Transfer vegetables to a large bowl and set aside. The zucchini will seem like it's underdone, but it will continue to cook as it sits. Do not overcook or it will be mushy.
Bring a large pot of generously salted water to a boil.
Cook pasta one minute less than package directions, reserving 1/2 cup of pasta water.
Strain pasta and transfer to the bowl of vegetables.
In the same saute pan over medium heat, stir together the lemon zest and juice, pasta water, and yogurt and bring to a simmer.
Add the pasta and vegetables back in and toss, cooking for 30 seconds to coat.
Remove from heat and add chopped basil before tossing again.