If desired, trim off the fat cap before moving forward with the cooking process. Some desire to leave the fat cap in place to provide extra moisture and flavor to the meat. And in some cases, the fat cap might have been removed for you before the meat was purchased.
After cooking, allow to rest, then place the steak on a cutting board with the top point of the tri tip being the closest to you.
Using a sharp knife, cut the steak in half from the top point along the large seam of fat to the opposite side, leaving two portions.
Working with the long half of the divided steak, rotate it about 30° towards yourself.
Starting from the uncut end, begin cutting thin slices across the grain until the side is complete.
Working with the remaining section, rotate the meat until the point is pointing to your left and cut thin slices across the grain until the section is complete.