The Clone Wars - S5E19 - "To Catch a Jedi"

Near the end of "To Catch a Jedi," Barriss Offee (whose identity isn't revealed until the next episode) steals Asajj Ventress's mask and lightsabers and, disguised as Ventress, attacks Ahsoka Tano.  During the fight, she slashes a pipe so that the resulting exhaust temporarily stuns Ahsoka.

While this is somewhat similar to an event in The Empire Strikes Back, where Luke directs exhaust from a cut hose in the carbon freezing chamber at Vader, creating enough of a distraction so that he can retrieve his fallen lightsaber, it actually has a closer analogue in an earlier episode of The Clone Wars, and this holds greater significance.

In "Cloak of Darkness" (S1E9), there's a lightsaber duel between Luminara Unduli and Asajj Ventress in which Ventress does the same thing:  she cuts a pipe in the Jedi cruiser so that the steam compromises Luminara's vision.  Ahsoka was present at the duel (albeit the later stages), and since Barriss is Luminara's padawan, it's likely that she's familiar with it, too.  In "To Catch a Jedi," she adopts this move as an-other facet of her disguise and an-other way to make Ahsoka believe that she is Ventress.

The Clone Wars - S5E19 - "To Catch a Jedi"

2:11 - Anakin (after Mace Windu says he thinks it would be better if Anakin didn't go after Ahsoka):  "Master Windu, with all due respect, she is my padawan."  In The Phantom Menace, Qui-Gon and Obi-Wan's pilot also says, "With all due respect" ("With all due respect, the ambassadors for the Supreme Chancellor wish to board immediately" [2:06]), and Obi-Wan says it in Revenge of the Sith while speaking to Mace Windu about Anakin ("With all due respect, Master, is he not the chosen one?" [40:32]).

4:21 - Barriss (to Ahsoka):  "Be safe."  Shmi Skywalker also says this to Anakin before the podrace in The Phantom Menace [57:00].

7:37 - Ahsoka (to Twi'lek boy):  "Thanks, kid.  I owe you one."  In Return of the Jedi, Han also tells Luke, "I owe you one" [37:21].

9:51 - Ahsoka (to Ventress, sarcastically):  "Good luck."  In The Empire Strikes Back, an unidentified Rebel pilot wishes Luke good luck [36:02] and Luke wishes Lando good luck [2:00:09], and in Return of the Jedi, Han and Lando wish each other good luck [Han to Lando at 50:33 and Lando to Han at 52:21].

13:26 - Ahsoka (after Ventress says, "It doesn't seem like you need my help"):  "That's not true."  Luke has a similar line in The Empire Strikes Back when Vader tells him about his father:  "That's not true.  That's impossible." [1:51:21].

13:58 - Ahsoka (after Wolffe says, "We're taking you in now, Commander"):  "That's not gonna happen.  Trust me."  Han also says, "Trust me" (to Leia) in The Empire Strikes Back [1:20:06].

18:49 - Barriss (in disguise as Ventress) slashes a pipe with a lightsaber so that the exhaust temporarily stuns Ahsoka, which is similar to what Luke does to Vader (with a hose) in The Empire Strikes Back [1:44:37].