Preparation Mix buttermilk, curry powder, 3 teaspoons salt, and pepper in large bowl. Add chicken; turn to coat. Cover; chill at least 4 hours or overnight. Remove chicken from refrigerator. Line 2 baking sheets with paper towels. Mix flour, chili powder, and 3/4 teaspoon salt in shallow dish. Mix tomatoes and next 3 ingredients in another large bowl. Add enough canola oil to 12-inch skillet to reach depth of 1/2 inch. Heat over medium-high heat to 375°F. Remove 6 chicken pieces from buttermilk mixture. Dip in flour mixture and turn to coat; shake off excess. Add chicken, skin side down, to skillet. Reduce heat to medium-low. Cover; cook until brown, about 12 minutes. Turn chicken over. Cook uncovered until cooked through, about 5 minutes for breasts and 10 minutes for legs and thighs; transfer to paper towels. Repeat with remaining chicken. (Salad and chicken can be made 2 hours ahead. Let stand at room temperature.) Add spinach to tomato salad; season with salt and pepper. Divide salad among plates; top with chicken.
Preparation Mix buttermilk, curry powder, 3 teaspoons salt, and pepper in large bowl. Add chicken; turn to coat. Cover; chill at least 4 hours or overnight. Remove chicken from refrigerator. Line 2 baking sheets with paper towels. Mix flour, chili powder, and 3/4 teaspoon salt in shallow dish. Mix tomatoes and next 3 ingredients in another large bowl. Add enough canola oil to 12-inch skillet to reach depth of 1/2 inch. Heat over medium-high heat to 375°F. Remove 6 chicken pieces from buttermilk mixture. Dip in flour mixture and turn to coat; shake off excess. Add chicken, skin side down, to skillet. Reduce heat to medium-low. Cover; cook until brown, about 12 minutes. Turn chicken over. Cook uncovered until cooked through, about 5 minutes for breasts and 10 minutes for legs and thighs; transfer to paper towels. Repeat with remaining chicken. (Salad and chicken can be made 2 hours ahead. Let stand at room temperature.) Add spinach to tomato salad; season with salt and pepper. Divide salad among plates; top with chicken.