Rinse the zucchinis and pat them dry. Trim off the ends, then slice into rounds about 1/3-inch thick. Lightly season the slices with salt and pepper, then arrange them in a single layer on paper towels. Let rest for 5 minutes, then blot the tops dry with more paper towels to remove excess moisture.

In a shallow bowl, beat the eggs until smooth. In a second shallow bowl, whisk together the flour and seasoning salt. In a third shallow bowl, combine the crushed Ritz crackers and Parmesan cheese.

Pour about 1 inch of oil into a large, deep skillet and heat over medium-high heat until it reaches 350°F on a deep-fry thermometer, or until a small piece of cracker sizzles immediately when dropped in.

Working with one slice at a time, dredge a zucchini round in the flour mixture, shaking off any excess. Dip it into the beaten eggs, letting the extra drip off. Finally, press it into the cracker mixture, coating all sides evenly. Place the coated slices on a plate or baking sheet.

Line a plate or baking sheet with a double layer of paper towels and set it near the stove.

Carefully place a few coated zucchini slices into the hot oil without overcrowding the pan. Fry for 2 to 3 minutes per side, until golden brown and crispy. Use a slotted spoon or tongs to transfer the fried slices to the prepared paper towel-lined plate.

Repeat with the remaining slices, adjusting the heat as needed to maintain the oil temperature. Serve the crispy fried zucchini warm with ranch dressing for dipping.