Martlesham murder trial: Jane Bartholomew had 20 head injuries
A mother-of-three was killed with a claw hammer by her partner who assembled a "killing kit" before attacking her, a court has heard.
Scott Ellis, 42, of Tunstall, denies murdering Jane Bartholomew, 39, at her house in Martlesham Heath near Ipswich in June.
The prosecution, outlining its case at Ipswich Crown Court, said she was "brutally executed".
Ellis will admit manslaughter on the grounds of diminished responsibility.
The trial was told Ms Bartholomew and Ellis had lived together in Melton, but sold their flat ten years ago and then lived apart while their relationship continued.
Peter Gair, prosecuting, said her killing had been "pre-meditated and planned" by the defendant who had been "motivated by anger and rejection as it followed the recent breakdown of their relationship".
The jury heard Ellis lived with his mother at Tunstall Green and had been told by his partner earlier in the year that unless he got a job and started to be a "proper dad" then the relationship was over.
Ellis told friends he had thought about killing her, the prosecution said.
The court heard he had confronted her in the car park of her workplace in Rendlesham on 22 May and put his hands around her throat, but this incident was not reported to police at the time.
The prosecution said the defendant bought the hammer and other items to produce a "killing kit".
Mr Gair said Ellis let himself into her home while she was taking their two youngest daughters to primary school, and then waited for her.
He killed her, tied her up and put plastic bags over her feet and head before leaving.
Her body was found by their older daughter when she returned from school in the afternoon.
Ellis was arrested late that evening after Ms Bartholomew's body was found.
The prosecution said he would claim a defence of manslaughter due to diminished responsibility.
The trial continues.