Take 2 frozen puff pastry sheets out of the freezer, and leave out for 5 minutes. Cut each sheet in half.
Make several holes in the pastry sheets with a fork. If the sheets already have holes in them, you can skip this step.
Slice the bananas into a bit less than 1cm thick slices (You can make 2 pies out of one banana.)
Layer the banana slices on each pastry sheet portion, overlapping each slice. Do the same for all 4 pieces.
Put the pies on a baking sheet lined with parchment paper.
Sprinkle the bananas with granulated sugar. Use as much sugar as you like. Even a pinch is delicious. Adjust the sugar, according to how ripe the bananas are.
Cut butter into thin strips, and lay on top of the banana.
Brush the pastry with egg yolk. No need to brush the bananas.
Bake the pies for 10 minutes at 410F/210C, then lower the oven temperature to 360F/180C and bake for another 10 minutes. Done!
You can sprinkle the pies with powdered sugar, or decorate with melted chocolate, or whatever you like. ♬ They're fine just as-is of course, too. ♡
Variation: Apple pie. Recipe ID: 1723647.
Please also see: Easy for beginners! Basic apple pie. Recipe ID: 1335485.
Story Behind this Recipe
I thought of this method when I was making sugar butter bread. By skipping the pie filling step, you can enjoy making pies quickly and easily. I've always wanted to make open-faced pies or tarts like this, so the first time I saw how nicely they came out, I was thrilled.
When sprinkling the pies with granulated sugar, try covering the bananas evenly. Avoid getting sugar on the pastry, and sprinkle on the bananas only. The bananas turn black if you leave the pies out for, but don't worry about that too much. If that bothers you, sprinkle the sliced banana with lemon juice beforehand.