BobUI has an embedded version of !Beautycase here's is Neal's explaination of how to use the "CreateBorder" function.

Lua Code:
  1. CreateBorder(myFrame, borderSize, R, G, B, uL1, uL2, uR1, uR2, bL1, bL2, bR1, bR2)

-> The name of your frame, It must be a frame not a texture
-> The size of the simple square Border. 10-12 looks amazing with the default beautycase texture
R, G, B -> The colors of the Border. r = Red, g = Green, b = Blue
uL1, uL2 -> top left x, top left y
uR1, uR2 -> top right x, top right y
bL1, bL2 -> bottom left x, bottom left y
bR1, bR2 -> bottom right x, bottom right y
Shorter method to add a border with no spacing

Lua Code:
  1. CreateBorder(myFrame, borderSize, r, g, b)

Or simple just one number (x) for the same distance on all corners

Lua Code:
  1. CreateBorder(myFrame, borderSize, r, g, b, x)

Get infos about the beautycase border on a frame
Lua Code:
  1. local size, texture, r, g, b, alpha = GetBorderInfo(myFrame)
Using the "SetBorderPadding" is even simpler.

Index a frame already border by !Beautycase and call the function so in the end it looks a bit like this: