Stir together all ingredients for sauce in a small bowl. Refrigerate until needed. Can be made two hours in advance.
Make Tomatoes:
The cornmeal-flour mixture sticks better to the inside of the tomato, so remove a sliver of each of the ends of the tomato and then cut into 1/4-inch slices. Depending on the size of your tomato you’ll likely get 3 or 4 slices.
Lay tomato slices on a towel and generously salt. Let sit at room temperature for 30 minutes. Place a second towel on top after 30 minutes to wipe off some of the salt.
In a shallow dish, add 1/2 cup flour.
In a second shallow dish, lightly beat egg and stir in buttermilk.
In a third shallow dish, combine 1/4 cup flour, cornmeal, smoked paprika and freshly ground pepper.
Heat a large skillet over high heat and add 1/4-inch oil. Heat oil to 375°F.
Dredge tomato slices in flour then dip in egg mixture and dredge in cornmeal mixture. Place tomato slices in hot oil and cook for 2 minutes on each side or until golden.
Drain on paper towels. Repeat until done, adding more oil if needed. Serve tomatoes warm.
Notes
* Since the tomatoes are salted at the beginning and the feta in the dipping sauce is salty, I recommend you taste the tomatoes and sauce together before adding more salt to the tomatoes once they are fried. * If you want to make this truly gluten-free use gluten-free flour (such as Cup4Cup Multipurpose Flour) in place of the all-purpose flour and gluten-free cornmeal (such as Bob’s Red Mill Gluten Free Medium Cornmeal). While cornmeal is naturally gluten-free, it could have cross-contamination depending on where it is produced.