Powder Fort

Powder Forte was a generic name for a spice blend used in the Middle Ages and into the Renaissance.

Just as when we say "Italian seasoning", there was no set list of ingredients, rather just the spirit of an idea that you attempted to capture. It may well be that various merchants selling it would even have kept their ingredients secret.

Ingredients suggested now for it include black pepper, cinnamon, cloves, cubeb, galingale, ginger, grains of paradise, long pepper, mace, nutmeg, etc.

Here's one interpretation for Powder Fort:

1 teaspoon cloves
1 teaspoon fresh nutmeg
1 teaspoon mace
1 teaspoon black pepper
1 teaspoon grains of paradise
3 teaspoons long pepper

And Another from Daniel Myers:

3 Tbsp. ginger 
1 1/2 Tbsp. cinnamon 
1 tsp. cloves 
1 tsp. cubebs 
1 tsp. grains of paradise 
1 tsp. black pepper 

One More from David Friedman

Powder fort is a spice mixture mentioned in various period recipes; we have not yet been able to find a description of what spices it contains. What we use is a mixture containing, by weight:

1 part ground cloves
1 part ground mace
1 part ground cubebs
7 parts ground cinnamon
7 parts ground ginger
7 parts ground pepper

This is a guess, based on very limited evidence; it works well for the dishes in which we have tried it.

Original Recipe in Libro di cucina/ Libro per cuoco there is a recipe for Fine spices for all dishes:

Specie fine a tute cosse.

Toi una onza de pevere e una de cinamo e una de zenzevro e mezo quarto de garofali e uno quarto de zaferanno.

Translation by Helewyse de Birkestad, OL (Louise Smithson):

Fine spices for all dishes (things)

Take one ounce of pepper, one of cinnamon, one of ginger, half a quarter (of an ounce) of cloves, and a quarter (of an ounce) of saffron.

Original Recipe in Libro di cucina/ Libro per cuoco there is a recipe for Fine spices for all dishes:

In addition, there is also a recipe for Black and strong spices for many sauces.

Specie negre e forte per assay savore.

Specie negre e forte per fare savore; toy mezo quarto de garofali e do onze de pevere e toy arquanto pevere longo e do noce moscate e fa de tute specie.

Translation by Helewyse de Birkestad, OL (Louise Smithson):

Black and strong spices for many sauces.

Black and strong spices to make sauces. Take half a quarter (of an ounce) of cloves, two ounces of pepper and an (equal) quantity of long pepper and nutmeg and do as all spices (grind).