Bring 500ml of full-fat milk to a simmer over medium heat. Add 2 teaspoons of loose-leaf Kenyan tea and stir continuously for 4 minutes as the milk threatens to boil over — keep stirring, that's the secret.
Add sugar to taste (we like 1.5 tsp), strain into warmed cups, and serve immediately with a Marie biscuit on the side.
The key is constant attention and full-fat milk. Skimmed milk simply does not work for doodh pati.