1Thinly slice the beef across the grain. Combine the eshalots, garlic, chilli and 2 teaspoons of the oil in a small food processor. Process until very finely chopped. Spoon into a bowl, add the beef and stir to coat. Cover and refrigerate until ready to cook.
2Place the noodles in a bowl, cover with hot water and stand 4-5 minutes until just tender, drain well.
3Heat the wok over high heat until hot. Add 2 teaspoons oil, then half the beef and stir-fry for 1 minute until sealed. Remove to a clean bowl. Repeat with oil and remaining beef.
4Add the remaining oil and swirl to coat the wok. Add the mushrooms and stir-fry 1 minute. Add the capsicum and beans and stir-fry for 30 seconds. Return all the beef to the wok with the hoisin and stir-fry 1 minute, then add the noodles and toss until well coated. Remove from the heat, add the basil and peanuts and serve.