Preheat the oven to 375°F (190°C). Line a large baking sheet with parchment paper or a silicone baking mat. Set aside.

Using a spoon, carefully scoop out the seeds from each zucchini half, creating a hollow center. Place the zucchini halves cut-side up on the prepared baking sheet. Brush with 1 tablespoon of olive oil and season lightly with salt and black pepper. Transfer to the oven and bake for 10-15 minutes, or until slightly tender.

In a medium bowl, combine sour cream, chili powder, ground cumin, smoked paprika, garlic powder, onion powder, salt, and black pepper. Stir until fully incorporated. Cover and refrigerate until ready to serve.

Heat the remaining 1 tablespoon of olive oil in a large skillet over medium heat. Add diced white onion and minced garlic. Season with salt and black pepper, then sauté for 4-5 minutes, stirring frequently, until the onion is translucent.

Add ground beef to the skillet, breaking it apart with a spatula. Season with chili powder, smoked paprika, and additional salt and black pepper as needed. Cook for 8-10 minutes, stirring occasionally, until the beef is fully browned. Drain excess fat if necessary. Remove from heat.

Remove the zucchini from the oven. Fill each hollowed half evenly with the seasoned beef mixture. Sprinkle half of the shredded cheddar cheese over the top. Return to the oven and bake for an additional 5-10 minutes, or until the cheese is fully melted.

While the zucchini bakes, combine diced avocado, cherry tomatoes, red onion, jalapeño, cilantro, and lime juice in a medium bowl. Season with salt and black pepper to taste. Toss gently to mix.

Transfer the baked zucchini boats to a serving platter. Top with the avocado-tomato mixture and remaining shredded cheddar cheese. Serve immediately with the seasoned sour cream dip on the side. Garnish with lime wedges and additional cilantro if desired.