Bring 2 inches of water and 1 1/2 teaspoons of the curry powder to a simmer in a medium straight-sided pan. Add chicken and poach for 12 minutes or until cooked through. Cool slightly, then chop into 1/2-inch pieces. Cool completely.
Meanwhile, slice tops off tomatoes and set aside. Scoop out tomatoes and turn upside down onto paper towels to drain.
Place remaining 1 1/2 teaspoons curry powder in a small glass bowl. Microwave 1 minute, until fragrant. Combine with chicken, mayonnaise and raisins. Place almonds in a second small glass bowl. Microwave 2 1/2 minutes to toast, stirring every 45 seconds or so. Add to chicken mixture, along with 1/4 teaspoon of the salt and the pepper. Flip over tomatoes and sprinkle with remaining 1/8 teaspoon salt. Fill with chicken salad and replace tops, if desired.