In a large mixing bowl, combine flour and salt. Incorporate cold vegan butter or oil until the mixture resembles coarse crumbs. Gradually add vinegar and cold water until a cohesive dough forms. Chill for at least 30 minutes.

Heat olive oil in a skillet over medium heat. Sauté onion and garlic until translucent, about 3-4 minutes. Add carrot, celery, and red bell pepper; cook for another 5-6 minutes. Stir in tomato paste, smoked paprika, cumin, lentils, and optional tofu, cooking briefly before mixing in herbs. Allow to cool.

Once chilled, divide the dough into 10 equal portions. Roll each into a 5-inch circle. Keep remaining dough covered.

Place 2-3 tablespoons of filling on one half of each dough circle. Fold over to create a half-moon shape and crimp edges to seal.

Preheat oven to 375°F (190°C). Arrange empanadas on a baking sheet lined with parchment. Brush tops with plant milk. Bake for 25-30 minutes until golden brown.

While baking, combine parsley, garlic, olive oil, vinegar, crushed red pepper, salt, and black pepper for chimichurri. Mix well.

Serve warm empanadas with chimichurri on the side.