Naturally, I just Googled it and searched for a recipe that listed things I already had in my place. And here we go!
4 tablespoons olive oil
1 tablespoon honey
1 teaspoon Dijon mustard
½ teaspoon kosher salt
¼ teaspoon freshly ground pepper
*I put them in Tazz and zipped it all together. I didn't follow the amounts of these ingredients because right off the bat, I had blended 4 grapefruits and wasn't exactly sure how much 1 grapefruit (juice only) would have yielded. So I just eyeballed everything. LOVED the Dijon part.
This turned out to be a really NICE dressing. You can taste the grapefruit but it wasn't overpowering. You can get the hint of Dijon... I might have went a tiny bit overboard on the honey.
**I have no idea why the text above is all wacky... just saying