Preheat your oven to 350 degrees.
Heat the olive oil in a skillet over medium heat. Add in the onions. Cook until translucent. Stir in the shredded meat and garlic. Cook for about 2 minutes. Mix in the tomato paste, taco seasoning, & water. Cook for about 10 minutes, or until all the liquid has rendered out. Stir in however much hot sauce you desire.
Mix 2 cups of masa with the baking powder, salt, and taco seasoning. Add the beef stock and mix to a crumbly consistency. Pour in the melted shortening and mix by hand until smooth.
Spray your muffin tins with non stick cooking spray. Roll the masa into golf ball sized balls. Place each ball inside of each muffin opening. Using your fingers, press the masa ball to form the inside of the muffin tin – making a cup.
Fill each masa shell with the meat mixture. Bake for 15-20 minutes.
Allow the tamale cups to cool for 5 minutes on a wire rack before removing them from the tins. To remove, use a small knife to lift one side, then gently lift them out with your fingers.
Garnish with crumbled queso fresco and cilantro. Serve warm.