1. Coarsely mash peas with fork. Stir in garlic, next 4 ingredients, and 1/2 tsp. salt. Stir until blended.
2. Spoon about 1/3 cup batter for each cake onto a hot lightly greased griddle. Cook cakes 2 minutes or until edges look dry and cooked; turn and cook 2 more minutes.
3. Stir together 1/3 cup sour cream, next 3 ingredients, and remaining 1/2 tsp. salt in a large bowl. Stir in slaw.
4. Place each cooked cake on a serving plate; top each with 2 tomato slices. Add salt and pepper to taste. Top with slaw; serve immediately.