Doughnuts should come quickly to top of fat, brown on one side, then be turned to brown on the other; avoid turning more than once. The fat must be kept at a uniform temperature. If too cold, doughnuts will absorb fat; if too hot, doughnuts will brown before sufficiently risen.
To test fat for frying: When the fat begins to smoke, drop in an inch cube of bread from soft part of loaf, and if in forty seconds it is golden brown, the fat is then of right temperature for frying. Many kinds of food may be fried in the same fat; new fat should be used for batter and dough mixtures (like doughnuts), potatoes and fishballs. After these, fish, meat and croquettes. Fat should be frequently clarified.
To clarify fat: Melt fat. Add raw potato cut in quarter-inch slices, and allow fat to heat gradually. When fat ceases to bubble and potatoes are well browned, strain through double cheesecloth, placed over wire strainer, into a pan. The potato absorbs any odors or gases, and collects to itself some of the sediment, remainder settling to bottom of kettle.
When small amount of fat is to be clarified, add to cold fat boiling water, stir vigorously, and set aside to cool; the fat will form a cake on top, which may be easily removed; on bottom of the cake will be found sediment, which may be readily scraped off with a knife.
One cup sugar, one cup sour milk, one level teaspoon soda in milk, two eggs, butter or lard the size of a small egg, a little nutmeg, and a pinch of salt, flour to roll out. Cut in rings and fry in hot lard.
One cup sugar, one cup sweet milk, two eggs, butter size of a small egg, one teaspoonful baking powder, a little salt. Mix in enough flour to roll in your hand. Always put a piece of apple or potato in the lard when frying doughnuts.
Yolks of four eggs, one cup of sugar, one cup of sweet milk, a little nutmeg, two teaspoons of baking powder; mix soft; cut out, and fry.
Two quarts flour, one cup sugar, one cup sweet milk, butter size of a small egg, four eggs, five heaping teaspoonfuls baking powder. Flavor with nutmeg.