Whisk first 10 ingredients in a large bowl. Fold in crab and 1 c gluten-free panko. Make sure that the crab is spread throughout the mixture, not in one big lump. Let stand for 10 minutes.
Scatter remaining 1c gluten-free panko on a plate.
Shape 16 crab cakes out of the crab mixture. Each cake should be about 2 inches across with about 1/4 c of the mixture. Press both sides of the patties into the panko on the plate.
Place each crab cake on a baking sheet covered with wax paper. Cover and refrigerate for at least an hour. You can keep them chilled and uncooked up to 1 day.
Melt 1 Tbsp butter with 1 Tbsp oil in a heavy, large skillet over medium-high heat. Once the butter/oil are hot, add crab cakes and cook until golden brown on both sides, about 2.5 minutes each side (5 minutes total). Add more butter and oil as needed.
Plate the crab cakes, adding sprigs of the fresh herbs to decorate the dish.
