"As a 73 year old newcomer to baking I have a small problem I need advise on. I like the HIGH CROWNED muffins I get in markets and restaurants, but when I try the recipes I get on the internet for jumbo berry, banana, and/or apple muffins, all I get, even when I FILL the muffin cups with batter, are small crowns on the muffins that seem to drop after a day of resting. I do not overmix the batter, and do live in a low altitude part of the country (Rhode Island). Do you have advise, and or a recipe that will result in HIGH CROWNED muffins?"