Make the Cupcakes:
Preheat oven to 350F. Line a Non-Stick 12-Cup Regular Muffin Pan with paper liners; set aside. You will likely have batter for a 13th or 14th cupcake, and I baked it in a cooking-sprayed mini loaf pan because my oven is small and that pan setup fits; discard extra batter if that’s easier.
In a large mixing bowl, whisk together the first 8 ingredients, through vanilla, until smooth.
Add the flour, baking soda, optional salt, and whisk until just combined; don’t overmix.
Using a 2-inch cookie scoop, place about 2 heaping tablespoons of batter per cupcake into each of the 12 cavities so they’re solidly 3/4-full. I poured the excess batter into the mini loaf pan.
Bake cupcakes for about 18 to 19 minutes (I baked the mini loaf for 23 minutes), or until domed, set, pale golden, springy to the touch, and a toothpick inserted in the center comes out mostly clean, or with a few moist crumbs, but no batter; don’t overbake.
Allow cupcakes to cool in pan for about 15 minutes before removing.
While cupcakes cool, make the frosting.
Make the Lemon Frosting:
Combine first 3 ingredients in a large mixing bowl, add about 1 cup confectioners’ sugar, and whisk to combine or beat with an electric mixer until smooth.
Continue adding sugar until desired frosting consistency is reached. Because I used light cream cheese, the frosting stayed on the runnier side. If you want frosting thick enough to pipe, do not use light cream cheese. If you like your frosting really piled on thick and high, make a double batch.
With a spoon, add 2 to 3 tablespoons frosting to the top of each cupcake and smooth with the back of the spoon if necessary. My frosting just ran naturally (from the light cream cheese). Optionally transfer frosting to a piping bag and frost the cooled cupcakes. I like the Wilton 1M tip for cupcakes.
Optionally, garnish each cupcake with a pinch of lemon zest.