Warm a large skillet over medium heat. Once hot, add pancetta and cook until crispy, about 5 minutes. Remove with a slotted spoon and set aside on a paper towel–lined plate.
In the same skillet, melt the butter over medium-high heat. Add shallot and cook until soft. Stir in corn and sauté until caramelized, 5 to 7 minutes.
Toss caramelized corn, crispy pancetta, pickled peppers, and brie in a large serving bowl. Garnish with scallions and lime wedges and serve warm or at room temperature.