I first discovered the Filipino lime, called calamansi, when I first visited the Philippines in the early 1970s. Milder and slightly less acidic than the common lemon or lime, the juice can be used in place their place in most recipes. Unfortunately, I haven't located a source of calamansi in Northern California.
So, it's no surprise that this recipe began life as calamansi muffins. The original recipe was adapted for the scale by a Filipina living in Southern California, known as @CarolineAdobo on Instagram. Caroline posted the recipe to her blog, When Adobo Met Feijoada, a reference to her Brizilian-born husband (@DadTheBaker). I'm envious because she has a local source of fresh calamensi.
I have posted the recipe in both weight and volume measurements. While I haven't tested the recipe for volume, give it a try if you don't own a digital scale. These muffins will make an appearance this summer at Oakland Feather River Camp.
Should you have a source for calamansi juice, whether fresh or bottled, feel free to substitute it for the lemon juice.
180 grams (1-/2 cups) all-purpose flour (100 baker's percent)
5 grams (1 teaspoon) baking powder (2.7%)
2 grams (1/4 teaspoon) salt (1.1%)
120 grams (1/2 cup) lemon juice (67%)
120 grams (1/2 cup) milk (67%)
112 grams (1/2 cup) softened unsalted butter (62%)
200 grams (1 cup) granulated sugar (111%)
105 grams (2 large) eggs (58%)
60 grams (1/2 cup) powdered sugar
15 grams (1 tablespoon) lemon juice
5 grams (1 teaspoon) butter
finely grated lemon zest
Preheat oven to 350 degrees F. Line a 12-cup muffin pan with cupcake paper liners. Set aside.
Measure the flour, baking power and salt into a small bowl. Sir to combine, then set aside. In a separate small bowl, measure the lemon juice and milk. Sir to combine, then set aside.
In a mixer bowl, cream butter on medium-high speed, adding one tablespoon of sugar at a time. Once added, cream until the mixture is light and fluffy, about five minutes. Scrape the bottom of the bowl with a rubber spatula.
Reduce speed to medium and add eggs, one at a time, beating well after each addition. Scrape the bottom of the bowl with a rubber spatula. Reduce speed to low. Add flour mixture in three batches, alternating with the lemon-milk mixture. Mix just until the batter is combined.
Fill each cupcake liner with 1/4-cup of batter. (A #16 scoop or disher with yield 12 muffins, and a #20 scoop will yield 15.) Bake at 350 degrees for 18 to 22 minutes, or until a cake tester comes out clean. Cool muffins on the pan for about 10 minutes, then transfer to a cooling rack. Cool completely before icing.
For the glaze, heat butter and lemon juice until butter has melted. Whisk together powdered sugar and the lemon-butter mixture until combined. Spread about one teaspoon over the top of each muffing. If desired, garnish with lemon zest. Let glaze dry and for a slight crust before serving.