Think of this crowd-pleaser as the love child of French onion soup and French onion dip: an ooey-gooey, salty, tangy Gruyère-filled dip with jammy caramelized onions. Gruyère is classic for that French onion soup flavor, but any fairly firm cheese like cheddar or Gouda will work—you can even mix and match if you’d like.
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6 – 8 Servings
Tbsp. plus 1½ tsp. extra-virgin olive oil
medium sweet onions, thinly sliced
garlic cloves, thinly sliced
tsp. crushed red pepper flakes
sprig thyme, plus more for serving
tsp. Diamond Crystal or 1¼ tsp. Morton kosher salt, divided
oz. cream cheese, room temperature
cup sour cream
lb. Gruyère, coarsely grated, divided (about 4 cups)
Freshly ground black pepper
red endive, leaves separated
Preheat oven to 350°. Heat 3 Tbsp. oil in a large skillet over medium. Add onions, garlic, bay leaves, red pepper flakes, 1 thyme sprig, and 1½ tsp. Diamond Crystal or 1 tsp. Morton kosher salt and cook, stirring occasionally, until onions are golden and jammy, 15–20 minutes.
Meanwhile, stir cream cheese, mayonnaise, and sour cream in a large bowl to combine (a few lumps are okay).
Remove bay leaves and thyme sprig from onions; discard. Transfer onions to cream cheese mixture. Add 3 cups Gruyère and season with pepper; stir to combine. Transfer dip to an 8″ cast-iron skillet or 2-qt. ovenproof baking dish and spread into an even layer with a rubber spatula.
Toss panko, remaining Gruyère, remaining 1½ tsp. oil, and remaining ¼ tsp. salt in a medium bowl to combine, then sprinkle over dip. Bake until heated through and top is lightly browned, 25–30 minutes.
Heat broiler. Broil dip until bubbling and golden brown, about 3 minutes. Let cool 5 minutes.
Scatter more thyme over dip and serve with baguette, pears, and endive alongside for dipping.
Do ahead: Dip (without panko mixture) can be made 3 days ahead. Cover and chill. Top with panko mixture just before baking.