Recipe(tried): Fluffy Muffin suggestions

I learned this from America's Test Kitchen and it works. Don't fill those muffins more than half. Any more batter in there and they will spread out not up. Also I sift all dry ingredients together in one bowl. Then all liquid and melted shortening or butter goes in another bowl and gets well beaten. The liquid is poured into the sifted and is BARELY mixed. Use a big spatula or wooden spoon to use as few strokes as possible to blend. It is OK to have flour still visible in the batter. We are talking minimal mixing here. Give these two hints a try and good luck.