1. Finely dice both the apples and the strawberries and then cut both the lime and the serrano pepper into fairly thick slices.
2. Layer all of the the different fruits in a tall pitcher, adding a dash of sugar in between every layer. For an interesting twist, you could use honey or agave instead of plain sugar.
3. After all of the fruit has been layered, add the sliced serrano chile and the remaining sugar. Let sit for 10 minutes.
4. Add the Viognier to the fruit and sugar mixture.
5. Add the white grape fruit juice and top it all off with the club soda. Place in the refrigerator to chill.
6. Once the sangría has chilled, bust out your favorite wine glasses. I like a lot of fruit in mine so I am not bashful about digging around for more berries. Just keep an eye out on those sliced serranos. They have a pretty respectable Scoville rating.
7. Garnish the drink with some fresh mint and serve.