In a large pot, over high heat, boil water, cinnamon sticks, cloves, tamarind, and tejocotes. After it starts to boil, lower the heat and simmer for about 10 minutes until the tejocotes are soft.
Remove the tejocotes from the heat, peel, remove hard ends, cut in half, and deseed. Return them to the pot.
Add guavas, apples, pears, sugar cane, prunes, orange slices, and piloncillo.
Simmer for at least 30 minutes, stirring gently. Discard cinnamon sticks and cloves.