Add the oil into a large saucepan and let it heat to 350 degrees. I used a candy thermometer to keep an eye on the temp.
Once the oil is up to temperature, add in 1 - 2 taco coats. Let it brown up for 1 minute and flip. Let it brown up on that side for 1 minute. Drain and place on a rack or plate lined with paper towels.
Repeat with all taco boats. Some may get air bubbles, it's nothing to worry about.
Preheat oven to 350 degrees.
Place the shells on a sheet pan.
Mix the chili dark chocolate and milk chocolate together. Add about 1 tablespoon to each taco boat. If there's extra, divide it amongst the taco boats to evenly distribute it.
Add a nice pile of marshmallows on top to cover all of the chocolate. It took about 7 - 10 marshmallows.
Place the boats into the oven and let it bake for 10 - 15 minutes until the marshmallows are golden brown and the chocolate is melted.
Remove from the oven and serve immediately!
Notes
To store any leftover Chili Smores Taco Boats, place in an air tight container and store at room temperature, out of direct sun light, for up to 3 days.