Preheat the oven to 350º Fahrenheit. Spray an 8x8 baking pan with cooking spray.
In a large bowl, use a hand mixer to mix together the sugar and butter.
Add the milk and vanilla extract and mix again. Scrape the sides of the bowl as you mix. The mixture will not be smooth, but that's ok.
Stir in the flour, baking powder and salt. Use the hand mixer to mix it in just until barely combined (on low speed). Scrape the sides of the bowl as needed. Don't overmix!
Fold in the coarsely chopped cranberries.
Pour and spread the batter in the prepared pan.
Bake for 35-40 minutes. Our cake took 37 minutes but it will depend on the type of pan you use. The cake should test done in the center (or bounce back when you touch it.)
Make the butter sauce:
Add the butter, sugar and half and half to a medium saucepan.
Bring to a simmer as the butter melts. Simmer for 5-10 minutes on low, stirring often.
The sauce will separate easily, so make sure you mix the sauce before pouring on the cake.
Serve the cake on plates with butter sauce poured overtop. Don't skip the sauce! The cake itself isn't overly sweet and I honestly don't love it plain, but add the butter sauce it and is AMAZING.
Store this cake at room temperature for up to 24 hours, then refrigerate any leftovers. Store in an airtight container.
**Please please read the note about the sauce. The butter sweet cream sauce is what makes this cake special. The cranberry cake on its own isn't very sweet. Make the sauce!!!The calories shown are based on the cake being cut into 9 pieces, with 1 serving being 1 slice of cake with sauce. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**