Ingredients
2   ripe medium plantains or 4 firm bananas
3  tablespoons margarine or butter
1/4  cup packed brown sugar
1  teaspoon vanilla
1/4  teaspoon ground cinnamon
2  tablespoons chopped pecans or walnuts, or slivered almonds, toasted
1/2  cup Crema Espesa (see Recipe below)
 

Directions
1. Peel and bias-slice plantains or bananas into 1/2-inch-thick slices (about 2 cups)
 

2. Melt margarine or butter in a large skillet. Add plantains or bananas to melted margarine or butter. Heat about 5 minutes for plantains (2 minutes for bananas) or just until warm and tender, gently stirring occasionally. Sprinkle with brown sugar. Stir gently until sugar melts.
 
3. Carefully stir in vanilla and cinnamon. Sprinkle with nuts. Serve immediately with Crema Espesa. Makes 4 servings.

Crema Espesa:

Ingredients
1  cup whipping cream (not ultra-pasteurized)
2  tablespoons buttermilk
 
Directions 
In a small saucepan heat whipping cream over low heat until warm (90 degree F to 100 degree F). Pour the cream into a small bowl. Stir in buttermilk. Cover and let the mixture stand at room temperature for 24 to 30 hours (do not stir) or until mixture is thickened. Store in a covered container in the refrigerator for up to a week. Stir before serving. Makes 1 cup. 
 

Source:  Better Homes & Gardens