Preheat the oven to 375 degrees F (190 degrees C). Generously butter a 12-cup muffin pan.
In a large bowl, whisk to combine the flour, baking powder, salt and onion powder.
In a pitcher or large measuring cup, combine the milk, raw egg, sour cream and melted butter; whisk until evenly incorporated. Pour into the bowl with the dry ingredients and stir with a rubber spatula until a thick batter forms. Fold in the bacon, scallions and Cheddar.
Using 2 spoons, drop heaped tablespoons of the batter into each cup of the prepared muffin pan. Add 1 hard-boiled egg to the center of each and press down so the egg meets the batter on the bottom of the pan.
Using the same two spoons, drop heaped tablespoons of batter over each egg, using the spoons to push the batter down to fully encase the egg.
Bake until the muffins are firm and golden brown on top, about 25 minutes. Remove from the oven and let cool slightly before unmolding the muffins from the pan. Enjoy immediately or refrigerate in an airtight container for up to 3 days.
Cook's Note: The all-purpose flour can be replaced with a gluten-free all-purpose flour.
The sour cream can be replaced with yogurt or buttermilk.
The cheese can be replaced with any shredded cheese of your choice -- or omit the cheese, if desired.
You can replace the raw egg in this recipe with flax or chia egg. You can also omit the hard- boiled eggs.
To hard-boil eggs: I like to boil 12 eggs then set them aside while I make the muffin batter. The method I use to hard-boil eggs is fool-proof and it goes like this: Start with a large pot full of cold water. Place your eggs in the water, making sure they are fully submerged. Bring the water to a boil, uncovered, over medium-high heat. This will take 10 to 15 minutes.
Once the water comes to a rolling boil, remove from the heat and cover the pot. Set your timer for 10 to 12 minutes (longer if you’re boiling a bigger batch of eggs). When the time is up, drain the eggs and run them under tepid water to stop the cooking.
When the eggs are cool enough to handle, crack them all over and peel while still warm. I promise you, this works like a charm every time.