Heat 2 tablespoons of the dressing in a large skillet on medium-high heat.
Add mushrooms; cook 5 minutes or until liquid is evaporated, stirring frequently.
Remove from heat; place in large bowl to cool slightly.
Meanwhile, cut the tenderloins lengthwise about halfway though meat.
Cover with plastic wrap or place in resealable plastic bag.
Flatten meat with meat mallet to 1/2-inch thickness.
Add soda crackers, pecans, parsley, parmesan cheese, salt and pepper to mushrooms; mix until well blended.
Spread half the mushroom mixture evenly onto each tenderloin; press stuffing gently onto meat.
Roll the tenderloins firmly, enclosing stuffing.
Tie with kitchen string in two to three places to secure.
Place tenderloins, side-by-side, in roasting pan; brush with remaining 2 tablespoons dressing.
Bake for 40 minutes or until meat is cooked through (160 degrees Fahrenheit).
Remove from oven.
Let stand 5 minutes.
Remove string before slicing.
How to Check Meat Doneness:
The easiest way to ensure that meat is cooked properly is to check the internal temperature. Using an accurate food thermometer will take away the guesswork. Simply insert the thermometer into the thickest part of the meat, avoiding any bones if present, and let stand until thermometer stops rising.