Preheat oven to 350 degrees F and grease a 9 x 13" cake pan or two 8" round cake pans.
In a medium mixing bowl, sift together the flour, baking powder, and salt. Add the sugar and combine.
Add the milk, vegetable oil, molasses, and vanilla and beat with electric mixer until combined. Scrape the sides and bottom to incorporate all dry ingredients.
Add the eggs and beat on medium for three minutes.
Fold the chopped rhubarb into the batter and pour into the cake pan.
Bake for approximately 55 minutes or until a toothpick inserted in the center of the cake comes out clean.
Notes
You may substitute butter for the vegetable oil by creaming together the butter and sugar and adding the milk and dry ingredients alternately as you beat the batter.You may substitute whole wheat pastry flour or regular flour for the unbleached flour.Try adding a teaspoon of cinnamon for a bit more flavor.I sometimes make a brown sugar crumble to top this cake. Melt 2 tbsps of butter, mix in 1/3 cup brown sugar and 1/4 cup flour. Sprinkle over the batter before baking.If you prefer to make 'Rhubarb Bread' instead of cake, pour the batter into two greased 9" x 5" loaf pans and bake for about the same length of time.