[UPDATED] Creating a 3-Tiered Dynamic Drop-Down List (NOT VBA)

Good evening everyone,

I am trying to apply a 3-tiered dynamic drop-down list in cell ranges named: BTClass, BTDes, and BTDes from the table named "tbl_BudgetList". Source data is from the cell ranges named: Classification, Category, and Description from the table named "til_RecordsList". I really don't know where to start, I've done some basic VBA coding before, but nothing like this. Does anyone have any ideas?

MOD EDIT: Non-VBA solution now required.