Peel the pineapple and cut it into 1/2-inch slices. Remove the core.
Grill the bell pepper (3-5 minutes per side; 12-20 minutes total), scallions (3-4 minutes per side; 6-8 minutes total), poblanos (3-5 minutes per side; 6-10 minutes total), and pineapple (3-6 minutes per side; 6-12 minutes total).
Transfer scallions, poblanos and pineapple to a cutting board and let cool. Place grilled bell pepper in a bowl and cover with plastic wrap until cool to room temperature. Scrape any really burt parts off, but don't worry about getting it all. Core and seed the bell pepper. Cut everthing into 1-inch pieces.
Place bell pepper, scallions, poblanos, and pineapple in a food processor and add ginger and mint. Pulse to coarsely chop, do not puree. Add lime juce and brown sugar and pulse briefly to mix. Taste for seasoning and add more lime juice and/or brown sugar as desired.