Preheat your oven to 400°F.
Slice the zucchinis in half lengthwise, then use a spoon to scoop out the centers, creating boats. Leave a little rim for structure.
Finely chop the scooped-out zucchini flesh and set it aside.
Place boats cut-side up in a baking dish. Drizzle with a little olive oil, and sprinkle with salt and pepper.
Pre-bake the boats for 10 minutes to soften slightly.
In a skillet over medium heat, heat 1 tbsp olive oil.
Add the ground chicken, season with salt and pepper. Cook until no longer pink, breaking it apart, then stir in the minced garlic, chopped zucchini flesh, and diced tomatoes. Cook for another 4–5 minutes until everything softens and combines.
Turn off the heat, then stir in about 1/4 to 1/3 cup pesto. Mix well.
Spoon the chicken mixture into the pre-baked zucchini boats.
Return the dish to the oven and bake for 15–20 minutes, or until the cheese is melted and bubbly.
