Prepare the garlic sauce by adding all ingredients, except the garlic, to a blender, and processing until very smooth.
Prepare cauliflower by chopping it to small pieces, and adding the pieces to a food processor bowl, and processing until it forms rice-sized pieces. Be careful not to overprocess the cauliflower or it will become mushy.
Add olive oil to a skillet over high heat, and stir fry the cauliflower for 3-5 minutes, until the cauliflower it hot. Avoid cooking too long or it will become watery.
Set the cauliflower rice aside, and rinse the skillet. Add sesame oil to the skillet, and place it back over high heat.
Add garlic to the hot skillet, and fry for 3-4 minutes, until the garlic just starts to brown. Add the prawns and broccoli, and stir fry 5-7 minutes.
Push the prawns and broccoli aside, and add the sauce to the skillet. Add the arrowroot, and then stir the sauce as it thickens.
Stir the shrimp and broccoli together with the sauce and remove from heat.