The preparation of aspic jelly consists of several steps:

1. A stock must be made using gelatinous products such as veal bones, calves’ feet or pork skin.
2. The stock must be reduced and clarified with the addition of aromatic products such as vegetables, wines, and seasonings.
3 Finally, the jelly must be tested to determine its consistency when cold.

To elaborate on making classical clear aspic jelly, here is the recipe broken down.
The ingredients for this recipe involve using:
Veal bones, that are cut into small pieces.
Calves’ feet , split in half lengthwise
Pork skin
Veal shank
Beef chuck
water
carrots
onions
leeks, white portion
Celery
Salt, pepper and sachet bag.
Method for making the aspic jelly
1. Blanch the bones, calves’ feet, and pork skin. 2. Rinse well in cold water, place in a pot and add veal shank and beef. 3. Cover with water and bring to a boil.
4. Skim boiling liquid, then add all the vegetables and seasonings. Cook for five or six hours on low heat. 5. Pour stock through a strainer, cool and remove all fat.
6. Reduce stock to one gallon.

To clarify the single gallon of stock you have made you will need the following ingredients.
Beef, lean ground
Leeks, celery and onion (finely diced)
Egg whites
Cold stock
Madeira, port or sherry

Method for clarifying the stock
1. Mix beef, vegetables and egg whites well in a large pot, then add one gallon of the cold stock.
2. Bring to a boil, stirring occasionally with a wooden spoon.
3. Simmer for one half to a full hour and strain through a cheesecloth. 4. Add one and a half cups of Madeira, port or sherry wine. In order to know the consistency of natural gelatin contained in the gelee, refrigerate a sample. If it sets to desired consistency, the aspic jelly is ready to be used. If the jelly is to be used to make aspic molds, it is necessary to reduce the stock by half in order to achieve the necessary strength.
Variations
The above recipe produces clear aspic jelly with practically no color. A light to
dark golden aspic jelly can be obtained by using a brown stock. For this stock, brown the bones, meat and vegetables and proceed in the same manner described for clear aspic jelly.
For poultry aspic jelly, substitute chicken or other fowl bones for veal bones and
shank. A game aspic jelly can be obtained by using veal bones with game bones added for special flavor.
Whatever the aspic to be produced, it is only necessary to brown the appropriate
bones and then follow the recipe for clear aspic jelly.

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