Mr Bharadwaj, 36, was a software engineer before he joined politics. "There is no machine in the world that can't be rigged," he declared during his demonstration, earning applause and desk-thumping in the AAP-dominated assembly.
He pressed on with a dare - "The next election is in Gujarat...give us the EVMs for just three hours...and I challenge that you (BJP) will not win even a single seat."
It takes 90 seconds to change a motherboard, he remarked.
The EVM he used, however, is a prototype and not one used by the Election Commission. "This is similar to the machine that people used to choose their 2014 government," he said.
Election Commission sources have challenged the party to try its skills in a hackathon that will be held at the end of May, for genuine voting machines. AAP has accepted, and Mr Bharadwaj is likely to represent the party at this challenge.
In a presentation of nearly an hour in the assembly, Mr Bharadwaj explained how EVMs can be tampered with, and how a secret code can be used to favour a particular party. "The BJP worker comes dressed like a voter. His job will be to enter a secret code in the machine," he said.
After making his point, he quipped, pointing at the three BJP lawmakers - "They are happy that they have won!"
"I have 10 years' experience in tech and engineering and I quit in 2013,"Mr Bharadwaj said at the start of his "tampering master class". "Despite the four-year tech gap, I can show you exactly how this is done."
The BJP, he commented, "has given me and my Chief Minister (Arvind Kejriwal, an IIT engineer) a chance to use our degree".
By the time he wrapped up his show-and-tell, social media was abuzz with comments.
Among those who praised the lawmaker was his party senior Kumar Vishwas.
Proud of having such a cool,logical and humours younger bro as our spokesperson @Saurabh_MLAgk God bless you Chotey