Fine Gael finally gets the battle-ready Varadkar it has yearned for as he takes aim at McDonald
Two days in a row, he has launched targeted and stinging attacks on Mary Lou McDonald that carried a very clear undertone.
By sarcastically praising her for "a flawless delivery of her script", Mr Varadkar was actually saying 'is that what Gerry and those shadowy men told you to say'.
Comparing her to Marine Le Pen was no accident either. Ms McDonald is one of Leinster House's best performers but what is actually behind the rhetoric and disruptive behaviour?
The Sinn Féin deputy leader rose to her feet on Tuesday to scold the Government over its record on childcare. There's no doubt families are struggling and the forthcoming Budget needs to cut them some slack.
But Ms McDonald's credibility falls flat when people think back to her defence of Mr Adams over the years. Like when he was severely criticised at the time for not informing authorities about child abuse claims against his brother Liam despite knowing for several years. At the time Ms McDonald said his critics were being "malicious". "Gerry at every stage did the best that he could in the context of that scenario."
On another occasion, Ms McDonald jumped to her boss's defence after he was arrested in connection with the murder of mother-of-10 Jean McConville.
She cried political policing and agreed with Mr Adams's summation that the brutal killing was something that "happens in war".
They are just two examples of incidents where Ms McDonald has undermined her own political capital in order to stick to the party script.
It's those kind of scenarios that Mr Varadkar will seek to remind the public of as Sinn Féin pushes Ms McDonald centre-stage ahead of the next election.
Marine Le Pen and scripts aside, the Taoiseach also took her to task over the lack of progress on re-establishing the Northern Assembly.
"It is because this is the attitude of Sinn Féin. They are constantly hectoring and making smart-aleck remarks. There is a lack of temperance, a lack of respect for other people and an inability to listen or to compromise," Mr Varadkar told an unruly Dáil.
This was the feisty, battle-ready Leo Varadkar that Fine Gael TDs have yearned for since his election as leader in June.
In an unprecedented scene, Ms McDonald marched across the chamber floor to tell him that she wanted him to write her a letter outlining what issues he believes Sinn Féin should compromise on.
Mr Varadkar would never write such a letter. It would inevitably find its way into Sinn Féin's 'An Phoblacht' and be used as propaganda to drive a wedge between Dublin and the people of Northern Ireland.
Instead the Taoiseach said it was up to Sinn Féin to make compromises because that's what it takes to form a coalition.
Therein lies the source of this row. Having run away from the possibility of governing after the last election in the Republic, Sinn Féin now wants to be in a coalition. Part of the strategy is creating an impression Gerry Adams is going away. Mr Varadkar clearly believes he won't. Just because Ms McDonald is the respectable face of Sinn Féin doesn't mean she can get a free pass from the sins of those she defends.