Chocolate Cherry Crock Cake: my slow-cooker cake recipe

As requested,
here's my version of the cake recipe I mentioned last week:

Chocolate Cherry Crock Cake
Prepare slow-cooker crock by generously buttering bottom and sides (up 2 inches at least)

• Stir together in saucepan:

2+ cups tart cherries
with 1/2 cup sugar
and 1/3 cup cornstarch
and stir on medium high heat, until thickened.

Spread hot cherry filling from above (or equivalent *canned cherries)
into bottom of buttered crock of slow cooker.

• Mix together in large bowl:

1/2 cup brown sugar
1/2 cup white sugar
1 cup gluten-free (or all purpose) flour
1/4 cup cocoa powder
1 tsp. baking powder
1/4 tsp. salt
then sprinkle this **dry mixture over the cherries in the crock of slow cooker.

• Dot top of mixture in crock with:

1/4 cup of butter, cubed
1/2 cup chocolate chips
Then pour over top:
1 (12 oz) can of Dr. Pepper soda

Cover with lid and cook on high for 2 hours.
Served warm with Vanilla Bean ice cream...
Yum!

A few notes:
Don't stir the layers together.  This is a very pudding-like cake so don't be surprised when it doesn't set up completely.
*I used my own fresh/frozen/thawed cherries, a quart-sized bag; but you can use a can of cherries.
I mixed up my own 'cake' mix, but if you'd rather, use a dry, **dark chocolate fudge cake mix.
Also, I had a black cocoa on hand, so if you use lighter cocoa, your cake won't be as dark looking.
Dr. Pepper soda has a cherry flavor, so it's the best to use if you have it.  I didn't, so used RC cola- a dark cola, instead.
I refrigerated my leftovers, but don't think that's really needed if you don't have fridge space.