Comment from Emmanuelle: I tried it tonight with lime instead of lemon (I live in a region with plenty of lime and no lemon) and a good quality, fruity olive oil. It was delicious. Thanks a lot!
In a small bowl, combine dry ingredients until well mixed. Using a fork, beat in egg, oil, lemon zest and lemon juice until well blended.
Pour into mug and microwave on High for 90 seconds.
Cool in mug and eat directly out of mug or remove carefully to a plate.
Comment from Emily: I also added a glaze of 3 Tbl sugar:1 Tbl lemon juice, heated in the microwave for 30 seconds or until it bubbles. I got that from Allrecipes.