Combine first 3 ingredients in a heavy skillet over medium heat. Toast 2 to 3 minutes or until aromatic. Remove from heat, and cool completely. Grind to a rough, coarse ground in a spice grinder. Combine fresh ground spices with tangerine zest, thyme, and salt. Rub spice mixture over shrimp.
Heat olive oil in a medium skillet over high heat. Add shrimp and cook, stirring constantly, 1 minute. Add garlic, reduce heat to medium, and cook shrimp 2 to 3 more minutes on each side, or until pink and cooked through.
Add rum and tangerine juice. Cook 1 minute, and stir in mint and cilantro. Serve immediately with bread for sopping up pan juices.