albertobali wrote:Sumatra Aceh Gayo
Sumatra Mandheling
Sulawesi Toraya
Bali Kintamani
Bali Pupuan (robusta)
The Mandheling, Toraya, and Pupuan will give a heavy body and low acidity; these will be your base. The Pupuan will give a dense crema, the Mandheling woody flavors and the Toraya spicy ones. Try these on their own in various proportions until you get the richest mouthfeel and roundest, deepest flavors.
The Gayo and Kintamani are lighter and more acidic; they will add high tones and aroma to the blend. Try them brewed and see what proportion of each tastes best to you.
Then combine them. Typically espresso blends use 50% to 70% base coffees, and 30% to 50% flavor coffees