I made this recipe the other day and they didn't come out quite right. I used 1% milk and part skim ricotta. I wasn't expecting a truly light and cake like muffin, but these were really heavier and denser than I expected, both the batter and the finished product. And there were little tiny bits of visible flour in the baked muffins. Do you think it's as simple as not having mixed them enough? I was taking to heart the usual injunction not to overmix muffins and I've never run into this problem before. Because the batter was so heavy, I got worried that I was overmixing and stopped before the batter was as mixed as it usually would be when I'm making muffins. (Is this making sense?) Also, the directions say to beat the wet ingredients and I took a whisk to them until they were completely mixed. Do you think it needed even more beating, maybe an electric mixer?