Place sun-dried tomatoes, olive oil, 3 tbsp water, horseradish, vinegar, and pepper in a blender and blend to a chunky mixture.
Cut off the firm white stalks of the collards. Fillet off the thickest parts of the remaining stalks that run down the backside of the leaves.
To make one wrap, place two collards head to foot (stalks at opposite ends) and partially overlap the leaves. Apply some of the tomato spread down the center lengthwise, then top with roast beef, carrots, and sprouts.
Tightly roll the leaves, beginning from the bottom wider end, tucking in the sides as you go. Cut in half to serve.