Line a baking sheet with parchment or wax paper.
Beat peanut butter, softened butter, vanilla, and salt until smooth and creamy.
Add powdered sugar gradually and mix until a soft, moldable dough forms.
Scoop 1-tablespoon portions and roll into smooth balls. Arrange on the prepared sheet.
Chill the peanut butter balls until firm, about 25 minutes.
Melt chocolate chips with coconut oil in short microwave bursts, stirring until glossy.
Insert a toothpick into each ball. Dip two-thirds into chocolate, leaving a peanut butter “eye.”
Set dipped buckeyes back on the sheet, smooth the toothpick hole, and chill until set.