I bought two for $5 with a coupon but they normally go for $4.89 in my area.
They kept it fairly simple with here with what's basically an onion, cheese, and beef combo. Thankfully, it worked out really well.
Unlike a lot of fast food cheese, there were two slices of natural Cheddar here. More importantly, I could actually taste the cheddar in every bite. It wasn't very sharp but it was tasty. Usually, I run into fast food cheese that just generically creamy and too mild to make an impact.
The onion trifecta was nicely showcased with a savory richness from the creamy aioli, a watery, sweet crispness from the grilled onions, and the slightly charred, light crunch of the crispy fried onions.
Overall, I really enjoyed Jack in the Box's Cheddar Onion Buttery Jack. I especially liked the bold onion quality and the cheddar.
Note: I know some of you have mentioned that you didn't like the mess of the butter (and it's actual butter that they use) or the more seasoned patty but you can actually just get the burger without butter or with a regular patty if you're looking to try it. I like the butter and the seasoning so it's great just the way it is for me.
Nutritional Info - Jack in the Box Cheddar Onion Buttery Jack (277g)
Calories - 969 (Calories from Fat - 583)
Fat - 65g (Saturated Fat - 27g)
Sodium - 1232mg
Carbs - 56g (Sugar - 13g)
Protein - 41g