Spray two 6 cavity donut pans with non stick spray. Set aside.
In a mixing bowl whisk together the flour, baking powder and salt. Set aside
In a large bowl or a stand mixer fitted with the paddle attached combine the oil, eggs, sugar and lemon zest. Using a sharp knife split the vanilla bean lengthwise. Scrape out the paste and add it to the bowl. Mix on medium speed until combined. Lower the speed to low and begin adding the flour mixture a little at a time alternating with the buttermilk. Mix until just combined. Do not over mix.
Spoon the mixture into the donut pan or fill a pastry bag or plastic zipper bag with the batter and snip off one end (this method is a bit easier)
Bake for 12-15 minutes or until the tops of the donuts are slightly springy. Cool on a wire rack completely before glazing.
To make the Glaze:
Combine the confectioners sugar, strawberries and heavy cream in a blender and purée until smooth.