Pretzel, potato chip, chocolate chip, and toffee blondies

My friend K's birthday was a few weeks ago.  She had a party and a friend of hers brought these blondie-brownie creations.  They had chocolate chips and pretzels, and I was informed that they also had potato chips (I didn't quite taste them), but what I did taste the AMAZINGNESS that they were.  I asked K to get me the recipe, and she told me she asked her friend.  But it's been over two weeks, and the recipe hasn't come.  There was only thing I could do: try and figure out a recipe myself. 

First, I searched for a blondie recipe.  No surprise that I found one on smitten kitchen.  And no surprise that her recipe is "infinitely adaptable" - perfect for the baker who wants to add her own add-ins!  Then, I did some searching to see if there was an already-published potato-chip-and-pretzel blondie recipe, and came across one (which, not surprisingly, used the same smitten kitchen blondie base).  That recipe called for white chocolate chips and butterscotch chips, but I'm not a huge fan of either of those, so I went with the original chocolate chips that were in the blondies I had originally.  Just for fun, I added some toffee chips (which I had in my kitchen cabinet).

And, very unlike me, I doubled the recipe (instead of my usual halfing it).  I have a few events I'd like to bring them to over the next few days.  I slightly underbaked them, since no one I know likes overbaked blondies or brownies.

Blondies:

Use the smitten kitchen base linked above. 

When adding the mix-ins, add:
1/2 cup crushed potato chips (I used ridged ones)
1/2 cup chocolate chips
1/2 cup crushed pretzels (I wanted to use mini pretzels, but the store was out)
1/4 cup toffee bits (optional)