Slice the green tomato into 2-3 even slices about 1/2" in width. Sprinkle the tops with a little salt. Lay the tomato slices in the crisping basket and set the dehydration function to 150° F for 15 minutes. See recipe notes if you do not have the dehydration function.
Remove the tomatoes from the basket and blot dry with paper towels. Preheat the Ninja Foodi on Broil with the basket in the inner pot for 10 minutes.
Combine the flour, cornmeal, 1/2 tsp salt, 1/4 tsp pepper in a shallow bowl. Combine the buttermilk and red pepper flakes if using into a second shallow bowl.
Dip each tomato slice into the buttermilk and then into the breading mixture. Coat lightly and shake off the excess. Set the slice on a plate and repeat with all the slices.
Take each coated slice of tomato and dip again into the buttermilk followed by the breading mixture. Spritz the top of each tomato slice with oil of your choice.
When the Ninja Foodi is preheated on broil for 10 minutes, spritz the basket with oil and place each slice of breaded tomato (oiled side down) in the basket in a single layer. Leave about 1/2" space between each tomato slice. Spritz the top of the tomato slices with oil.
Turn the Air Crisp function on 390° and Air Crisp for 20 minutes. Flip at 10 minutes. I recommend checking on the tomato slices and remove when crispy and brown. Cool on a cooling rack.
Serve & Enjoy with your favorite dipping sauce