Butter pecan is almost a delicious ice cream flavor. I mean, the base flavor is butterscotch, and how can that be bad, right? The problem is the pecans. While I love them in pie or pralines, they just don't belong in ice cream. It's the texture, really. Those dry, cold, crumbly bits of nut totally mess up the creaminess of the ice cream.
Friendly's has, for many years, offered Butter Crunch. This ingenious flavor replaces the pecans with pieces of butterscotch candy. You know those yellow-orange butterscotch discs that you can buy at the drug store, but you always want to bite them instead of suck on them for fifteen minutes? Imagine someone breaking one of those into small, not-too-sharp pieces, and scattering them throughout butterscotch ice cream. See what I mean? A step up from butter pecan.
I don't think Friendly's is a national brand, but my mom has reported finding Butter Crunch in the freezer at a Stop & Shop as far away as New Jersey; your mileage may vary. If you find yourself in greater Boston, many local ice cream shops carry ice cream from a nearby dairy, Richardson's, which also makes butter crunch.