Heat your oven to 425℉. I know that seems high - but we turn down the temp after the first 5 minutes...so carry on!
Melt a stick of butter and let it cool. You can whisk up the melted butter and try to incorporate air / cool temperatures into the butter to get it to cool faster. You can also put the melted butter into the fridge to try to ensure it is cooled down.
Zest 3 lemons into the Sugar in a large bowl. Stir and let it sit.
Squeeze lemons to get ¼ C of juice. Use the balance of lemon juice in your drinking water or with your dinner or .... ? Zested lemons will last a couple of days if tightly wrapped and refrigerated.
Mix lemon juice into Sugar mixture.
S-L-O-W-L-Y add the milk to the butter - while whisking. If you are anything like me - your butter wasn't very cool and your milk is cold... adding milk slowly to the butter will help prevent the butter from clumping back up.
Add eggs, sour cream, FdS (or vanilla extract) and cooled butter/milk into the Sugar mixture and stir / whisk.
Combine the dry mixture in another bowl and whisk.
Combine the dry into the wet mixture and stir gently with a spatula until just combined and there isn't any dry flour.
Line muffin tin with paper liners. Or not. See Note below!
Load Muffin Tin with batter. You can use an ice cream scoop or other tool (large spoon?) to load up the mix into 12 muffin tins.
Bake at 425℉ for 5 minutes and then turn down to 350℉ and bake another 14 - 16 minutes. (Mine were perfect after 14 minutes). Watch for browning and use a toothpick inserted to confirm done-ness.
Let the muffins cool in their tin for 5 minutes, then move to a cooling rack.
If you are a sugar-a-holic - you could make a lemon drizzle (stir to combine) and add to the top of your muffins. The calories below DO NOT include the additional drizzle.