Trim all silver skin and excess fat from both tri-tips using sharp knife. Pat dry with paper towels.
In large container, combine 1 gallon raw honey with 1 cup red chili flakes. Stir thoroughly to distribute flakes evenly throughout honey.
Submerge both tri-tips completely in honey mixture, ensuring they're fully covered. Weigh down if needed to keep submerged. Cover container tightly and refrigerate.
Turn tri-tips once daily for 5 consecutive days, checking that they remain fully submerged. Add more honey if level drops.
After 5 days, remove tri-tips from honey. Scrape off excess honey, leaving thin sticky coating. Season generously with kosher salt. Rest 15-30 minutes at room temperature.
Preheat grill to 450-500°F for high direct heat on one side, indirect heat on other side. Clean and oil grates.
Sear tri-tips over high direct heat 2-3 minutes per side on all surfaces until honey caramelizes into dark crust. Watch carefully to prevent burning.
Move tri-tips to indirect heat side. Close lid and cook until internal temperature reaches 135°F for medium-rare or 140-145°F for medium, about 15-25 minutes.
Remove from grill and rest 10-15 minutes tented with foil. Slice against the grain in quarter-inch slices, adjusting cutting angle when grain direction changes.
