Rub the oil (or use a cooking spray) on both sides of the tuna steak(s). 

Season generously with salt and pepper (for prettier rolls, you can omit the pepper, but I like the way it tastes). 

Heat a steel or cast iron pan over high heat and add the tuna steak(s). 

Sear for 1 minute per side. Take off of the heat and let rest for 5 minutes. Slice thickly against the grain. 

Pour a couple inches (5cm) of warm water into a casserole dish or large plate that can fit the entire rice paper sheet. 

Place a sheet in the water and let it soak for 20 seconds.

Take it out and lay it on a flat surface in front of you. 

An inch (2.2cm) away from the edge closest to you, lay down 1-2 slices of tuna, 2 slices of mango, a large pinch of lettuce, a basil leaf, and then top with 2 slices of avocado. 

Lay the edge closest to you over or onto the pile of ingredients. 

Fold the left and right sides over like a burrito, then roll the ingredients away from you, tucking them into the rice paper with your fingers. Roll as tightly as possible, keeping the sides closed, until you get to the end. The rice paper should adhere to itself. 

Set aside and start on the next. You should end up with 12 rolls. 

This is a challenging thing to do (I’m still not very good at it), so don’t be frustrated when your first few fall apart. Keep trying and you’ll get better at it quickly. 

Mix together the sauce ingredients in a small bowl. 

Slice the rolls in half. 

Arrange the rolls on a platter and serve immediately with the sauce. Enjoy!