Toss zucchini and salt together in a large bowl. Transfer the zucchini to a colander; place the colander over the bowl. Let drain until water has released from the zucchini, 30 minutes to 1 hour.
Position a rack in the top third of the oven; preheat to 475°F. Line a rimmed baking sheet with paper towels; arrange the drained zucchini in a single layer on the paper towels. Top with additional paper towels; firmly press down to dry the zucchini.
Discard the paper towels. Drizzle oil over the zucchini; toss to coat. Arrange the zucchini slices along the edges of the baking sheet. Bake until browned in spots on the bottom, about 15 minutes. Remove from oven (do not turn oven off). Flip the zucchini; arrange in a single layer on a work surface lined with paper towels. Let cool for 5 minutes.
Meanwhile, stir together sour cream and everything seasoning in a small bowl.
Using the bottom of a measuring cup, gently smash each zucchini round to about ½-inch thickness. Using a spatula, return the smashed zucchini to the baking sheet. Sprinkle evenly with cheese. Bake until the cheese has melted, 3 to 5 minutes. Transfer to a platter; top with the sour cream mixture, bacon and chives. Serve immediately.
