• 1/2 cup olive oil
• 3-4 tbsp vinegar (white vinegar works best and balsamic generally works the worst)
• 2 tbsp shoyu
• 1 tbsp grated sushi wasabi
• A few drops of sesame oil

Mix this junk up in a shaker or something and bam, you have it. As for the taste, it's difficult to describe, but it has hints of woodiness (if you use balsamic I find this becomes obnoxiously overpowering) and spiciness. Overall, the taste is best approximated as tangy. It tastes quite different than you'd expect from reading the ingredients, try it out.