For the waffle batter: whisk together the sourdough starter, flour, sugar, and buttermilk until fully combined. Cover the bowl with plastic wrap and let sit on the counter overnight at a cool room temperature (65-70°F).
For the chicken: add the chicken, buttermilk, 1 tsp salt, 1 tsp black pepper, ½ tsp garlic powder, ½ tsp cayenne pepper, paprika, sage, and thyme to a medium sized bowl and mix until evenly coated. Cover with plastic wrap and chill in the fridge overnight.
Sourdough Waffles
Right before you are ready to make the waffles, whisk together the eggs and melted butter and add to the waffle batter. Then mix in the baking soda and salt (the batter will bubble and get fluffy).
Heat your waffle iron and spray with a non-stick pan spray, then pour the waffle batter onto the hot iron and cook according to manufacturers instructions and repeat! Note: most waffle makers will cook your waffles in about 4-6 minutes. You should see steam escaping from the sides during cooking, so watching for the steam to stop is a good way to gauge how long to cook your waffles.
Keep your waffles warm and crispy by sticking them on a baking sheet in the oven set to about 200°F. These also freeze great! Store in a freezer bag for up to 6 months. When you're ready to eat, remove from the freezer and let thaw for about 10 minutes, then pop them in the toaster!
Buttermilk Fried Chicken
Start heating about 1-2 inches of canola oil in cast iron or dutch oven (about 2-3 cups depending on the diameter of your pan) over medium-high heat. You want the oil to reach about 350-370°F. You can tell it's ready by dropping a little bit of flour in the pan and if it sizzles, it's ready!
Mix together the flour, 1 tsp salt, 1 tsp black pepper, ½ tsp garlic powder, and ½ tsp cayenne pepper. Dredge the marinated chicken tenders in the flour mixture and fry for about 7-9 minutes. Turn the tenders with tongs every 2-3 minutes so they get evenly browned. Only fry about 3-4 tenders at a time so as not to crowd the pan (you can do more at a time if you have a wider pan).
After frying the tenders, you can keep them warm and crispy on a baking sheet in the oven at about 200°F. You don't want to just put them on a plate and cover them as that will create steam which will ruin the crispy texture!