I start by shredding my cooked chicken into bite-sized strands so it layers nicely inside the tortilla. Then I slice the tomatoes and shallot thin, so they don't overwhelm each bite. I separate the romaine leaves and give them a quick rinse and pat dry, because wet lettuce makes for a soggy wrap.
Next, I cut the avocado in half, remove the pit, and slice it into thin strips. I squeeze fresh lime juice over the slices right away, since this keeps the avocado from browning while I finish prepping everything else. This little step makes a real difference in how fresh the wrap looks later.
I lay my tortilla flat on a plate or board and spoon the ranch dressing right in the center. Using the back of the spoon, I spread it out evenly, leaving a small border around the edges. This base layer is what holds everything together once you start rolling.
Now comes the fun part. I start with a layer of romaine, then pile on the shredded chicken, followed by avocado, tomato, and shallot. I top it all off with slices of brie, since the cheese sits best near the top before rolling. I finish with a light drizzle of sweet and sour sauce for that sweet-tangy contrast.
I fold in both sides of the tortilla about two inches, then roll it up tightly from the bottom, tucking the fillings in as I go. If the wrap looks like it wants to spring open, I just slide a toothpick through the middle to hold it in place until I'm ready to slice or serve it.