In a medium bowl, combine the flour, salt sugar baking powder and cream of tartar. Pour into a food processor, and add the shortening. Pulse to mix until the mixture resembles coarse meal.
Stir in the cheese with a fork. Mix in the milk and water until fully combined. Fold in the jalapenos.
Turn the dough onto a floured surface, and flatten into a rectangular shape. Cut the dough into squares.
Place the dough onto a baking sheet lined with parchment paper, and divide into balls. Place biscuits at least 1 inch apart and bake for around 15 minutes, or until golden brown.
Notes
If you don't have a food processor, you can use a pastry cutter or two knives.
These biscuits are best enjoyed the day they are baked. If you have leftovers, store them in an airtight container in the fridge. When you want to eat it, heat it in the microwave for 20-30 seconds.