Preheat the oven to 400°F (200°C) and line a large baking sheet with parchment paper or a wire rack.
Pat the chicken drumsticks completely dry with paper towels. Toss them in a large bowl with the baking powder, salt, and crushed black peppercorns until evenly coated.
Drizzle one tablespoon of olive oil over the drumsticks and toss to combine. Arrange the chicken on the prepared baking sheet, ensuring they do not touch.
Bake for 20 minutes, then flip the drumsticks. Scatter the cherry tomatoes and lemon slices around the chicken.
Continue baking for another 20 to 25 minutes until the skin is golden and crispy, and the internal temperature reaches 175°F (80°C).
Remove from the oven and garnish with fresh parsley and thyme. Serve immediately with the green dip and white dip on the side.