To Make the Garlic Yogurt Sauce
Mix yogurt, mint, lemon juice, oil, honey, and garlic in a small bowl; season with salt and pepper. Cover; chill.
To Make the Fritters
Grate zucchini, potato, and onion on the large holes of a box grater or by using the larger grater disc with your food processor. Transfer to a mesh sieve set over a bowl and toss with 2 tsp. salt. Let vegetables sit until they release their liquid, 30-40 minutes.
Mix eggs, garlic, cumin, thyme and mint in a medium bowl; season with salt and pepper. Gather up half of zucchini mixture in a kitchen towel; squeeze out excess liquid This is important; getting rid of extra liquid will help them be crispy). Add to bowl with egg mixture and repeat with remaining zucchini mixture. Sprinkle flour and baking powder over; mix gently.
Heat vegetable oil in a large skillet over medium-high heat. Working in batches, spoon scoops of mixture into skillet, flattening gently with a spatula. Cook until golden brown and crisp, about 3 minutes per side. Transfer to a wire rack; season with salt.
To serve, drizzle yogurt sauce with olive oil and top with more herbs; serve alongside warm fritters.
Garnish with tomatoes.