Lemon Mug Cake

Lemon mug cake is a single-serving dessert mixed and cooked in one microwave-safe cup. Fresh zest supplies more lemon aroma than juice alone, while a modest amount of juice keeps the batter from becoming wet. Microwave power varies, so use appearance and temperature cues instead of relying only on seconds.

Recipe details

• Yield: 1 serving
• Prep: 5 minutes
• Cook: about 60 to 90 seconds
• Equipment: 12- to 14-ounce microwave-safe mug, fork, measuring spoons, thermometer

Ingredients

• 4 tablespoons all-purpose flour
• 2 tablespoons granulated sugar
• 1/4 teaspoon baking powder
• Pinch of fine salt
• 3 tablespoons milk
• 1 tablespoon neutral oil or melted butter
• 1 tablespoon beaten egg
• 1 teaspoon finely grated lemon zest
• 2 teaspoons lemon juice
• 1/4 teaspoon vanilla
• Confectioners’ sugar or berries, optional

Method

1. In the mug, stir flour, sugar, baking powder, and salt with a fork. Break up every lump before adding liquid.
2. Add milk, oil, measured beaten egg, zest, lemon juice, and vanilla. Stir into a smooth batter, scraping the bottom and corners. Wipe batter from the upper inside wall.
3. Microwave uncovered on high for 50 seconds. Check the center, then continue in 10-second bursts until the surface looks set and springs back lightly. The center should reach 160°F.
4. Let the mug stand for 2 minutes because it will be very hot and continues cooking. Dust lightly with sugar or add berries before eating.

Cues and troubleshooting

Choose a mug with ample headspace because the batter rises quickly. Stop heating once no wet batter remains; too much microwave time creates a tough, rubbery cake. A damp-looking surface is normal, but liquid batter is not. If flour pockets remain, stir more thoroughly next time. Measure the egg rather than adding a whole one, which would overwhelm this small batter.

Substitutions

Orange zest and juice make an orange version. Dairy or unsweetened nondairy milk both work. Melted butter gives richer flavor, while neutral oil keeps the crumb softer. A cup-for-cup gluten-free flour blend may work but can need another teaspoon of milk. Use only microwave-safe ceramic or glass without metallic trim, cracks, or an unsafe decorative glaze.

Safety and storage

The mug and cake can be hotter than they appear, so use an oven mitt and allow the rest period. Do not eat uncooked batter because raw flour and egg can carry harmful organisms. This dessert is best freshly made. If necessary, cover and refrigerate it within two hours for one day, then warm briefly; expect a firmer texture.

Microwaves below 900 watts may need additional short bursts, while high-powered models may finish sooner. Keep the mug centered on the turntable. Make one cake at a time so the timing remains predictable, and never cover the mug tightly because steam must escape.