Bring a large kettle of water to a boil over high heat. Stir in salt and vinegar. Add cauliflower and boil for 3 minutes, then drain and set aside.
Melt butter in a large skillet over medium heat. When melted, add sage leaves and fry until bubbling ceases and butter is lightly browned.
Transfer sage leaves to a paper towel to drain and sprinkle lightly with salt.
Add cauliflower to the browned butter and cook until cauliflower begins to brown in spots, about 5 minutes. Add bread crumbs and dried sage, stir, and continue to cook until bread crumbs are crispy. Season to taste with salt and pepper.
Serve topped with reserved crispy sage leaves.