Baked Reuben Dip

I've been making this Baked Reuben Dip for ever. I got the original recipe from my ex brother in law some 25 years ago. Originally the recipe called for sliced Buddig roast beef, and it was fine. However, I have found that using roast beef from the deli makes for a much better dip. The original recipe, at least as I learned it, was for