A photo like it (a café de olla) · Luisalvaz (CC BY-SA 3.0) via Wikimedia Commons · source
The clay-pot coffee of Mexican kitchens and old cafés like Café de Tacuba: coffee simmered with raw cane sugar, cinnamon bark and orange peel, warm and gently spiced.
60 to 80 g (2 to 3 oz) piloncillo (or dark brown sugar), roughly chopped
1 stick Mexican cinnamon (canela, the soft, flaky Ceylon kind), about 10 cm (4 in)
2 strips orange peel, no pith
1 clove (optional), 1 star anise (optional)
50 g (1/2 cup) dark-roast coffee, ground medium-coarse
How to make it
Infuse (8 min): In a clay pot (an olla) or saucepan, bring the water, piloncillo, cinnamon, orange peel and spices to a boil, stirring until the sugar melts. Lower the heat and simmer 5 minutes.
Steep (5 min): Turn off the heat, stir in the coffee, cover and leave 5 minutes. Don't boil the coffee or it turns bitter.
Strain (1 min): Pour through a fine sieve lined with a paper towel or a cloth into a jug.
Serve: Hot, in clay mugs if you have them, with pan dulce: a concha is ideal.
Tips
Taste for sweetness after straining: piloncillo varies. Add more while it's hot.
Clay gives it its earthy taste; season a new olla by boiling water in it first.