Prepare first box of gelatin according to package instructions in small bowl. After all water has been incorporated, make and ice bath in larger bowl. Place smaller bowl into the ice bath, and stir with a spoon until gelatin is partially set. (Alternately, you can set bowl in fridge for a few hours until set)
Once jello is partially set, add half your strawberries and mix. Pour this mixture into pretty glass bowl, and place into fridge to fully set, about 2 hours.
When jello is set, pull glass bowl out of fridge. Spread sour cream over the jello, then spread crushed pineapple over sour cream. Return to fridge while you prepare next layer of jello.
Prepare the second box of gelatin same as the first, adding strawberries when partially set as before. Pour into glass bowl.
Top decoratively with sliced bananas.
Put jello into fridge, and allow to set for a few more hours, or ideally over-night, before eating.