Heat 1 t oil in 12 inch nonstick skillet over med-high until just smoking. Add beef and cook, breaking up pieces til no longer pink. Drain beef well and set aside. Mash beans to a paste; set aside.
Heat 1 T oil in now empty skillet over med til shimmering. Add onion and cook til lightly browned, about 5 minute Stir in jalapenos, garlic, cumin and chili powder and cook til fragrant, about 30 seconds. Stir in mashed beans, tomato sauce, water, cilantro, 1/2 t salt, and 1/2 t pepper. Stir in drained beef and cook, stirring occasionally, til thickened and begins to sizzle, about 10 minute Season with salt and pepper to taste. Transfer to a bowl; set aside to cool, about 20 minute.
Line a rimmed baking sheet with parchment paper. Set wire rack inside second rimmed baking sheet. Wrap 6 tortillas in clean, damp kitchen towel; place on plate and cover plate tightly with plastic wrap. Microwave til hot and pliable, about 90 seconds. Working with 1 tortilla at a time, brush edges of top half with egg. Place row of 3 level T filling across lower half of tortilla. Fold bottom of tortilla up and over filling, then pull back on tortilla to tighten it around the filling. Roll tightly and place seam side down on lined baking sheet. Cover with damp towel. Microwave remaining 6 tortillas and repeat the filling process. They can be made 24 hours ahead, covered with damp towel, wrapped tightly in plastic and refrigerated.
Adjust oven rack to middle position and heat oven to 200 degrees. Heat remaining 1 c oil in 12 inch nonstick skillet over med-high til it reaches 350 degrees. Using tongs, place 6 taquitos, seam side down, in oil and fry until golden, about 5 minute Flip and fry til other side is golden, about 3 minute Transfer to wire rack, and keep warm in oven. Repeat with remaining taquitos.
Meanwhile, combine avacados, sour cream, water, lime juice and cilantro in bowl and mash with fork or potato masher til smooth. Season with salt and pepper to taste.