Fold the batter over until it is barely mixed. Don't stir it excessively. You can tell when your batter is properly mixed when the batter appears bumpy in the bowl and falls in lumps off the spoon. It produces a baked muffin with an even texture with no large holes or tunnels, which is moist and tender. Properly stirred muffins are best for cycling, where durability is an important factor.
An overmixed batter brings out the gluten in the flour, making the dough smooth and elastic. The batter will stretch when lifted with a spoon. The resultant muffins are tough, dry, and are more prone to crumbling, and have an uneven texture with holes and tunnels.
Choosing a Muffin Pan
Choose a solid, well-constructed muffin pan. It should have beaded, rounded corners, and the cups should be seamless.
Shiny muffin pans reflect heat whereas dull or dark pans absorb heat. Dull pans result in a browner crust and you may with to lower the temperature by 12 C (10 F).
Filling the Pan
Muffins are sized by measuring the diameter of the wides portion. A miniature muffin is 2 inches across, medium is generally 2 3/4 inches, and a large muffin is 3 1/2 inches diameter.
To keep crusts from burning, always try to leave one muffin cup with water, which prevents burning and reduces uneven baking. If the batter will fill only half of the muffin tray,fill the remaining cups with water to avoid heat damage to the metal.
To grease a pan quickly and cleanly, slip your hand into a plastic sandwich bag, then grease. While shortening is often used to grease pans, butter or leftover bacon grease are better alternatives. When making extra large muffins, grease the top of the muffin pan to prevent the muffin tops from sticking to the pan.
If a pan becomes encrusted, soak it in cold water sprinkled with baking soda and allow it to stand for several hours. Wash as usual.
When doubling a recipe, cut back on seasonings such as salt, cinnamon, ginger, cloves, nutmeg, and the like. For a double batch, adjust seasonings by only 50% as a rule of thumb.
If using non-instant milk powder as a substitute for milk, mix dry powder with other dry ingredients, and add the required volume of water to the wet mixture. Otherwise, the milk powder will become lumpy.
Serving and Storing
Muffins are best eaten within two days of baking. Store fresh muffins in a container with a loose-fitting top, as they can become sticky in an air-tight container.
When freezing muffins, allow them to cool fully before wrapping in a plastic bag or air-tight plastic container. Muffins freeze best for one to two months.
Frozen muffins are best reheated by baking at 200 C (400 F) for 25 minutes when covered lightly in foil. Muffins which have cooled to room temperature are reheated by again covering lightly with foil and heating at the same temperature for 10 minutes. Another approach is to sprinkle water on the inside of a paper bag, fill it with muffins, close the bag tightly and bake it at 150 C (300 F) for 20 minutes.
To freshen stale muffins, sprinkle water on the inside of a paper bag, fill it with muffins, and bake it for 20 minutes at 150 C as above.
Leftover stale muffins can be frozen in a plastic bag and used later as a quick topping for a casserole. Crumble the muffin, dot the top with butter and sprinkle it with cheese. This is especially good with savoury or whole wheat muffins.