A neighbour strangled Joanna Yeates then went shopping in Asda with her murdered body in his car boot, a court has been told.
Vincent Tabak texted his girlfriend to say he was bored just minutes after murdering the 25-year-old landscape architect, a jury was told.
CCTV footage showed Tabak then wandering the aisles at an Asda supermarket, in Bedminster, Bristol, before dumping her body.
Tabak - who admits manslaughter but denies murder - did not even know his victim's name, Nigel Lickley QC, for the Crown, said.
Shortly after killing blonde Miss Yeates, Tabak sent his girlfriend a text message: "Miss you loads. It's boring here without you Vxx".
Mr Lickley told Bristol Crown Court: "It would appear this message was sent after he had killed Joanna Yeates, a message to his girlfriend indicating that he was bored."
He then went to the 24-hour supermarket to buy rock salt - for melting ice - along with crisps and beer. "It must be that the body of Joanna Yeates was in the boot of his car at the time of his visit to Asda," Mr Lickley said. Tabak went to the Asda store twice and did his shopping on the second visit.
In the days after killing the landscape architect, Vincent Tabak attended parties and dinners as he coolly maintained the pretence of a worried neighbour, the prosecution claims.
The bespectacled Dutch engineer looked on from the dock as Mr Lickley said: "He was able to mislead and manipulate others and to hide his inner feelings. He was in complete control and knew what he was doing."
Less then two hours after killing Miss Yeates, Tabak sent a further text message to his girlfriend. The message said: "How are you? I am at Asda buying some crisis. Was bored. Can't wait to pick you up." Mr Lickley said Tabak had meant "crisps" rather than "crisis" in his text message.