Start this recipe by very quickly frying the beef strips in a wok with the vegetable oil. As soon as it is ready, add in the sesame oil and toasted sesame seeds and remove off the heat. Next, fill a large dish with about 1″ of warm water. Submerge 1 spring roll wrapper in the water completely, wait for it to soften for about 10 seconds, then place the sheet on a clean work surface. Lay on a piece of salad, followed by a little of the sesame beef. Stack on 2 strips of the red bell pepper, yellow bell pepper, carrot, asparagus, and avocado in the lower 1/3 section of each sheet, towards the center. Scatter some chopped coriander, 2 pieces bamboo shoots and sliced green onions on top of the stack to finish. Roll up spring roll and fold right and left sides of the wrapper in towards the center of the roll. Continue rolling upwards (away from you) until you get a completed roll. Repeat the rolling process for all 12 rolls. Next, make the dipping sauce by placing the fish sauce, sugar, water, lime juice, garlic and chili in a bowl and stir until the sugar is dissolved. To serve, cut each roll in half and place decoratively on a large platter. Serve the dipping sauce in a small ramekin alongside the vegetable glass spring rolls.