A favored haunt of Bayern Munich players, it was here that the team's coach Pep Guardiola sat with Thomas Tuchel, who was taking a year-long break from his own fledgling managerial career.
So engrossed were the two that the waiting staff dared not interrupt an their intense three-hour discussion as salt and pepper pots were shifted across the table, with each man offering his own view on the beautiful game.
At the time, Tuchel was on a sabbatical after a successful five-year stint coaching Mainz. On Sunday, the two will be in opposing dugouts as Bayern welcome Borussia Dortmund -- a fixture known in Germany as "Der Klassiker."
Seven matches into the new season, reigning German champions Bayern hold a four-point lead over second-place Dortmund at the top of the Bundesliga.
Under former coach Jurgen Klopp, Dortmund provided a real challenge to Bayern's traditional dominance of Germany's top flight, winning the title in 2011 and 2012, while finishing up runners-up to the Bavarian club in 2013 and 2014.
However, last season Dortmund's form nosedived -- the club even flirted with relegation -- before four consecutive wins in February helped propel Klopp's side to Europa League qualification.
But that topsy-turvy campaign was enough to prompt Klopp to take his own sabbatical.
Klopp's successor Tuchel has made quite an impact since taking over, guiding Dortmund to 11 successive wins across three competitions, though "The Black and Yellows" have slightly faltered of late drawing their last two league games.
Even Sunday's 2-2 draw had the silver lining in that Dortmund striker Pierre-Emerick Aubameyang scored twice, becoming the only player in Bundesliga history to score in the first seven matches of the season.
Tuchel was never a top player. A talented defender, he played just a handful of matches in Germany's second division and around 50 third-tier games, before his playing career was cut short by injury at the age of 25.
Although he graduated with a diploma in business economics, Tuchel quickly realized that his passion lay in coaching.
After coaching at various youth levels at VfB Stuttgart and FC Augsburg -- the club he had won the German Youth Cup with as a player in 1991 and 1992 -- Tuchel became Mainz 05's Under-19 coach in 2008.
Tuchel quickly showed his promise as a coach by winning the German Under-19 title -- with a Mainz team including German World Cup winner Andre Schurrle -- against favorites Dortmund who boasted the talents Mario Gotze, who is now a Bayern Munich player.
At the time, Mainz's senior team had just been promoted back into the Bundesliga under Norwegian coach Jorn Andersen. But, just a few days before the start of the 2009-2010 campaign, manager Christian Heidel fired Andersen after Mainz was eliminated from the German Cup first round "due to a difference of vision."
Despite him having never played a match in the Bundesliga, and even more significantly, having never coached a senior team before, Mainz owner Christian Heidel opted to appoint Tuchel.
It wasn't the first time that Heidel had raised a few eyebrows when choosing a coach.
In 2001, Heidel appointed Klopp as Mainz's head coach, even though he was still playing for the team. It was a decision which paid off not just for Mainz, but also for German football as Klopp became one of the best, and most popular, coaches in Bundesliga history.
Tuchel's coaching philosophy is characterized by thorough planning, structure and thought.
-- Flexibility is key, with Tuchel's match planning mirroring the opposition's set-up and he will change the behaviors of his own players during the week's training sessions and even during matches.
-- Tuchel's teams never play 11 vs.11 matches during training, always playing on small pitches with limited space. His playing style centers around plenty of balls played diagonally along the floor.
-- To force his players to play diagonal balls, they occasionally play on diamond-shaped pitches.
Tuchel focuses not only on what happens on the playing field but also on the psychological aspects of the game.
He strongly believes that football at the highest level is a player's game and not a coach's game. The most important job of the coach is to support and help his team.
The group is always the most important element of Tuchel's philosophy. Every morning he wants his players to greet each other with a handshake, as if to say, "we're looking forward to work today."
It's a philosophy that appears to have resonated with Aubemayang telling CNN: "It's really good to work With Tuchel we have a lot of pleasure to train every day."
That desire to constantly improve his players is partly based on a famous quote from the legendary basketball star Michael Jordan.
"I've missed more than 9,000 shots in my career. I've lost almost 300 games. Twenty six times, I've been trusted to take the game winning shot and missed. I've failed over and over and over again in my life. And that is why I succeed."
Similarly, Tuchel believes that forgetting about your successes and instead remembering your failures is what makes you a better player.
During his sabbatical, Tuchel never stopped working but traveled the world to glean new ideas. He visited many countries, clubs and coaches as he searched for fresh ideas. And he didn't just look for inspiration in football, but from other sports as well.
He practices what he preaches, looking after his own nutrition and fitness in a very disciplined way. He has a strict separation between his professional life and private life; he talks about an 80:20 split in favor of football.
Many people were intrigued as to why Tuchel took a sabbatical.
It's likely because his approach as a coach is so demanding -- both physically and mentally. He needed that break to recharge and come back stronger.
When Dortmund travel to Munich this weekend, Tuchel and Guardiola won't go to Schumanns to discuss football. They are opponents now. They don't have time for late-night football philosophy.