Ganache-filled cupcakes fallen

Hi, all! I'm attempting to make cupcakes with ganache baked into the center. The cupcake itself is exactly what I want, flavor and texture-wise. I just can't get the ganache to bake in properly.

I've adjusted my cupcake recipe twice and used 2 techniques for adding the ganache. First, I made a hole in the batter and put the ganache into it. Disaster. Second, I just put the ganache on top. Not quite as bad but still not good. My cupcake batter is very thick so I'm wondering if I need to try a different recipe. Recipe and pics below.

This recipe has been adjusted for my high altitude and very dry climate:

1 stick unsalted butter

5 tbs brown sugar

5 tbs granulated sugar

1 egg

1 tsp vanilla

1 cup all purpose flour

1/2 tsp salt

1/4 + 1/8 tsp baking soda (odd measurement due to high altitude)

2 tbs milk

1/2 cup mini chocolate chips

Cream butter and sugar until fluffy; add egg and mix for 1 minute; add vanilla; gradually add dry ingredients and mix until incorporated completely. Mix in milk as needed. Stir in chocolate chips.

This is the version of the recipe that I used when I put a teaspoon sized dollop of chilled ganache on top of the batter. I baked them at 350 for about 14 minutes. 

Any ideas, advice, tips, tricks to share? These are just for my own use so I'm just playing around and have no deadline or pressure to make them right.

Thanks!

Really?   I was hoping to ge this kind of effect but with my own cupcake recipe:

http://www.bettycrocker.com/recipes/molten-chocolate-cupcakes/8c33caa3-6e41-41d2-8b78-f5b0d1f3da02

I'll try filling them after the fact with the next batch. Thanks!

Thanks KoryAK, and everyone else. I will go with filling them with a softer ganache. I've never filled cupcakes so I'll try both methods to see which works best for me. I'll try again this weekend and let you know how they turn out!

AmandaKB6, I did that the first go around and they cratered, too, even worse than the second batch (which is in the pictures). I have to contend with all the issues associated with baking at over 6000 feet above sea level so that could have something to do with it, too.

LisieAn, the ganache had been in the fridge overnight, so it was really well-chilled. I did have a thought along your lines though and considered freezing it.

Thanks again, everyone, for the help!