How to Make It
In a large pot of boiling salted water, cook yellow squash and zucchini until tender, about 5 minutes; drain. Trim ends and halve each squash lengthwise. Scoop out centers and chop flesh.
Warm oil in a large skillet over medium heat. Add turkey and cook, stirring, until no pink remains, about 4 minutes. Stir in chopped squash and remaining ingredients through tomato. Cover and cook until vegetables are just tender, stirring twice, about 10 minutes. Taste and season with salt and pepper.
Spread 1 tsp. taco sauce into each squash half. Mound with filling and sprinkle with cheese. Top with sour cream and serve.