This recipe is a childhood favorite that my grandma passed to my mom and now I am passing to my own kids! It is quick and easy, and great for summer picnics. Plus, the little ones are fascinated when I tell them the boiling water is the 'mystery' behind the cake. Also great with a scoop of vanilla ice cream on top!

Anonymous

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Recipe Summary

prep:
15 mins
cook:
45 mins
total:
1 hr
Servings:
8
Yield:
8 servings
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Ingredients

8
Original recipe yields 8 servings
The ingredient list now reflects the servings specified
Ingredient Checklist
Topping:

Directions

Instructions Checklist
  • Preheat oven to 375 degrees F (190 degrees C).

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  • Place blueberries in a deep 8-inch pie pan; drizzle lemon juice over blueberries.

  • Beat 3/4 cup sugar and butter together in a bowl using an electric mixer until creamy. Sift flour, baking powder, and 1/4 teaspoon salt together in a bowl. Mix milk, alternating with flour mixture, into creamed butter mixture until batter is just combined. Pour batter over blueberries.

  • Combine 1/2 cup sugar, cornstarch, and 1/2 teaspoon salt together in a bowl until thoroughly mixed; sprinkle over batter. Pour boiling water over sugar mixture.

  • Bake in the preheated oven until a toothpick inserted in the middle of the cake comes out clean, 45 to 50 minutes.

Cook's Note:

If top begins to brown too much, lower heat for last 15 minutes.

Nutrition Facts

249 calories; protein 2.4g 5% DV; carbohydrates 50.3g 16% DV; fat 4.9g 8% DV; cholesterol 12.7mg 4% DV; sodium 301.6mg 12% DV. Full Nutrition

Reviews (10)

Read More Reviews

Most helpful positive review

Rating: 5 stars
07/24/2013
We really liked this cake. I would say it is more like a cake-like pie. I guess my pan wasn't deep enough because it overflowed...thank goodness I had the pan on top of a cookie sheet. Read More
(4)

Most helpful critical review

Rating: 3 stars
09/30/2019
2.5.15 ... https://www.allrecipes.com/recipe/233342/blueberry-mystery-cake/ ... I've been in the overflowing blueberry syrup situation before - & having homegrown, very juicy blueberries nearly ensures a mess - soooo to minimize, I used an 8x8 glass dish. It was fine. I added 2T cornstarch to the berries (very juicy ones) & reduced sugar in the cake part to 1/3c. 'Done in 35- 40 minutes. Done = it bubbles five minutes. The cake part reminded me of a sugar cookie. It's crisp on top, but soft on the blueberry side. A bit too much sugar. 'Not the prettiest dish, but you want to eat it, not just look at it. Read More
(2)
12 Ratings
  • 5 star values: 8
  • 4 star values: 2
  • 3 star values: 2
  • 2 star values: 0
  • 1 star values: 0
Rating: 5 stars
07/24/2013
We really liked this cake. I would say it is more like a cake-like pie. I guess my pan wasn't deep enough because it overflowed...thank goodness I had the pan on top of a cookie sheet. Read More
(4)
Rating: 5 stars
01/10/2014
Thanks for the reviews! Glad you are enjoying this family favorite! If you are having issues with the pie pan overflowing (mine is really deep) feel free to make in a larger casserole dish. I sometimes make in a casserole just to have a prettier dish to take to a party. Read More
(2)
Rating: 3 stars
09/29/2019
2.5.15 ... https://www.allrecipes.com/recipe/233342/blueberry-mystery-cake/ ... I've been in the overflowing blueberry syrup situation before - & having homegrown, very juicy blueberries nearly ensures a mess - soooo to minimize, I used an 8x8 glass dish. It was fine. I added 2T cornstarch to the berries (very juicy ones) & reduced sugar in the cake part to 1/3c. 'Done in 35- 40 minutes. Done = it bubbles five minutes. The cake part reminded me of a sugar cookie. It's crisp on top, but soft on the blueberry side. A bit too much sugar. 'Not the prettiest dish, but you want to eat it, not just look at it. Read More
(2)
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Rating: 3 stars
08/05/2015
Tasty & easy but not much different than other fruit cobbler type recipes. No one jumped up for seconds. Read More
(1)
Rating: 4 stars
08/11/2013
this is quite good. i was looking for a recipe to use the last of my blueberry crop and this fit the bill. the only one thing i would change is to add a bit of cornstarch to the berries before putting in the pan. it is a bit soupy when serving. other than that no complaints. delicious quick and easy to make. thanks for the post yogurt4k i will make again! Read More
(1)
Rating: 5 stars
07/27/2013
This was easy and was a big hit at my spinning group. I wish I read the first review I didn't protect my oven and it over flowed. Otherwise I loved it and will make this again. Read More
(1)
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Rating: 5 stars
03/10/2017
I have made this Mystery Cake 5 times in the last week and half! My husband loves it! I made it with blueberries the first two times blueberries and blackberries the next two times and right now it's in the over with peaches! It's really really good and really easy to make! most ingredients you would have in the house except maybe the fruit. It cooks up beautifully with a nice crust and I would consider this more of a cobbler type recipe than a cake. During the summer we have access to beautiful marion berries which will be wonderful with this recipe! I highly recommend this have posted photos on FB and given the recipe out to several people already! It's going to be a staple dessert in my house! Read More
Rating: 5 stars
08/18/2019
I’ve made this recipe several times and just love it. Instead of a pie dish I use a cake pan. It’s guaranteed not to spill over in the oven. I usually add a few more berries or even other soft fruit I have on hand. The recipe should say ‘scoop’ rather than ‘pour’ the batter over the berries. Read More
Rating: 5 stars
04/01/2018
I will make this again it's wicked unusual! Read More