Bring a large bot of salted water to a boil, then add the sweet potatoes. Simmer just until fork tender, about 10 to 15 minutes depending upon the size of your potato chunks. Drain, gently and quickly rinse with cold water, then set aside.
If necessary, cook the bacon according to one of my easy methods listed below. Once cool, crumble it into a large bowl. Add the celery and green onions.
Prepare the mustard dressing: In a small bowl or large measuring cup, whisk together the jalapeno (or fresno chile), mustard, garlic, vinegar, olive oil, salt, and pepper.
Add the sweet potatoes to the bowl with the bacon, drizzle with the dressing, then toss gently to combine. Taste and season with additional salt/pepper as desired. Serve warm, chilled, or at room temperature.
I've enjoyed this sweet potato salad cold, at room temperature, and even warmed up as a side at dinner. Store leftovers in the refrigerator for up to 4 days.