Munster were 10-3 ahead at the break after O’Donnell’s first effort but were staring down the barrel as the Blues fought back.
Daf Hewitt and Lewis Jones crossed the whitewash either side of O’Donnell’s second to establish a slender lead.
But Laulala, who spent three seasons in the Welsh capital, crashed through his former team-mates to snatch a victory from the jaws of defeat — Munster’s third in a row and fifth on the bounce against Cardiff.
The former All Black admitted it was a bitter-sweet feeling but he was relieved that Munster escaped with the hard-fought victory.
He said: “All I could think about was getting the ball to the try line — it was a relief for the boys.
“I felt for the Blues boys but at the end of the day I’m a Munster player now and it was a good win for us.
“We had a lot of international boys away and a lot of young guys out there but we managed to find a way.
“We knew the Blues would be up for it at the Arms Park but it showed we are going in the right direction.”
One current Irish international on display was Ronan O’Gara, who was released to Munster for the Pro12 clash and he started at fly-half with Ian Keatley moving into the centre.
The veteran fly-half has been sidelined since the beginning of October but was aiming to prove his fitness ahead of Ireland’s autumn series and came through unscathed to hand Declan Kidney a major boost.
But Munster were hit by an early onslaught from the Blues, who were still hurting from last week’s humiliation at the hands of Leinster.
The hosts came out firing and were quickly rewarded with a Jason Tovey penalty — but Munster came storming back.
They launched a counter-attack with Keatley and Luke O’Dea making the initial inroads. Rob Penney’s men continued to pile the pressure on the hosts and when the ball was recycled and spread left Keatley once again ghosted through and slipped an off-load to O’Donnell to score.
O’Gara made no mistake with the conversion and Munster soon had the Blues under the pump again. They kicked to the corner and launched a rolling maul but the Blues’ Irish number eight Robin Copeland came away with the ball and cantered into the Munster half.
He was hauled down but got his pass away as the Blues looked for quick ball. But O’Gara saved the day with a cynical infringement at the breakdown that earned him 10 minutes in the sin-bin.
The Blues attempted to make their numerical advantage count andthreatened in attack but Munster soaked up the pressure and O’Gara returned to the pitch without his side conceding a point.
Keatley continued to impress in attack and his break led to Munster’s next points with O’Gara knocking over a second penalty to make it 10-3 at the interval.
But the Blues began the second half with a bang and levelled the scores inside five minutes. From a solid scrum Hewitt hit an angle off Ceri Sweeney and he sliced between O’Gara and Keatley to score, with the replacement fly-half converting
Sweeney added a penalty but Munster quickly wrestled the lead back as O’Donnell bulldozed through the Blues.
However the helter-skelter nature of the game continued as Jones pounced on the loose ball after Peter Stringer was charged down to touch down.
That looked enough but Laulala had other ideas.
Scorers for Cardiff Blues: Tries: D Hewitt, L Jones; Con: C Sweeney; Pens: J Tovey 2.
Scorers for Munster: Tries: T O’Donnell 2; C Laulala; Cons: R O’Gara 3, Pen: O’Gara.
CARDIFF BLUES: D Fish; T Williams, G Evans, D Hewitt, T James; J Tovey, L Jones; C Ma’afu, R Williams, T Filise, L Reed, J Down, L Hamilton, J Navidi, R Copeland.
Replacements: O Williams for T Williams, 58; C Sweeney for Tovey 44; S Hobbs for Ma’afu, 60.
MUNSTER: F Jones; D Howlett, C Laulala, I Keatley, L O’Dea; R O’Gara, D Williams (P Stringer 52); M Horan (J Ryan 60), M Sherry, S Archer; D Foley (I Nagle 60), B Holland; Dave O’Callaghan, S Dougall (P Butler 24), T O’Donnell.
Replacements: P Butler for Dougall, 24; P Stringer for Williams, 52; I Nagle for Foley, 60; J Ryan for Horan, 60.
Referee: Andrew McMenemy (SRU)