Soak prunes overnight in water to cover.
Place prunes and water in a saucepan; simmer 15 minutes. Remove from heat; drain prunes, reserving 3 tablespoons liquid. Slice prunes three-quarters open. Set aside.
Combine cream cheese, pecans, and reserved liquid; mix well. Stuff each prune with 1 1/2 teaspoons cream cheese mixture. Serve on lettuce leaves, if desired.