Hi guys. I'm very new to the baking world. What is the best, two tier cake size that will feed 40 people? I'm getting conflicted info between Wilton and earlene's chart. I want to be pretty occurate. It without being short or wasting too much cake. Thanks!

Most use the Wilton chart as do I.  If you're looking for round two tiers, you could either do a 9"-6" for 44 servings or an 8"-6" for 36 servings.  8"-6" square tiers would give you 40 servings.

My cakes are taller than the 4" cake that Wilton uses for their chart, so I tend to go for less servings (like the 8-6 round tiers).  

Thanks!