In a medium bowl, sift together the flour, salt and baking powder. Set aside.
With a stand-mixer or hand beater, cream the butter, orange juice and zest and sugar until well combined and light.
Add the eggs, one at a time, beating well after each addition.
Beat in half the flour mixture, followed by half the ricotta. Beat well, scraping down sides of bowl. Repeat with remaining flour and ricotta.
Gently fold in banana pieces.
Pour the mixture into a greased and buttered springform pan and bake at 370 degrees for 45 minutes.
Cake will be done when it is nicely browned and a skewer inserted in the center comes out clean.
Cool on a wire rack and dust with powdered sugar.