This is the other lovely dessert (Helen & Alexandra, that microwave was WAY off):
1/3 c dark rum
1/4 c dark brown sugar
1 tbs unsalted butter
1/4 tsp vanilla extract
1 tbs fresh lemon juice
zest of 1/4 lemon
1 thin slice fresh ginger, grated
Combine rum, sugar, butter, lemon juice, zest, and ginger (all but vanilla and bananas) in a 4-cup glass measure. Cover tightly with microwave plastic wrap. Cook at 70% for 3 min.
Remove from oven, uncover, and add 1/2 tsp vanilla extract. Stir.
Peel and quarter bananas (crosswise and lengthwise) and place in a single layer in a deep dish. Pour rum mixture over and cover tightly with microwave plastic wrap. Cook at 70% for 3 min. (Bananas should lose their firmness and break down somewhat.)