We eat a lot of muffins in this house - at least a batch a week. They are just such a quick and healthy snack to grab on the way out the door, and my kids will eat anything in muffin form. I had a bunch of grapefruit from a big sale, and I wanted to do something other than eat it raw. It was so hard to find grapefruit recipes online! I couldn't find anything that looked both appealing and healthy, so I improvised. This is a combination of several recipes for other citrus muffins that I found both online and in a few cookbooks.
2 C flour
2 t baking powder
1/4 t baking soda
1/2 t salt
1/2 C white sugar
2 T grapefruit zest
3/4 C freshly squeezed grapefruit juice
1/2 melted butter
1/2 C ground flax seed
Combine dry ingredients. Wisk zest, juice, butter, eggs, and flax. Stir into dry ingredients until just blended. Spoon into 12 lined muffin tins. Bake at 350` for approximately 20 minutes.
I put a little streusel topping before baking the muffins pictured, but I would leave that out next time, so I left it out of the recipe above.