LOL Your sandy soil is mixed with sand? That's alright. My clay soil is mixed with clay and rock. I really benefit from the Ruth Stout No-Till Heavy Mulch method.
I know it will break down over the year and get thinner, but I've got at least 4 inches of shredded leaves/grass clippings with 4 inches of tree mulch on top of that over all of the garden.
I've already started putting down old carpet and padding over the area that I will incorporate into the garden next year. A year to smother out the grass makes it a cinch to dig, and then layers of compost and more mulch will keep it grass free. What's not to love?
/johnny