Combine all the ingredients together in a mixing bowl. Mix well with a spoon or with your clean hand. Cover the bowl with clingfilm and refrigerate for at least 1 hour, preferably overnight.
Take out the sausage mixture from the refrigerator and using your hand, stir and squeeze the sausage mixture until the mixture is slightly sticky. Alternatively, mix the sausage mixture with a stand mixer fixed with a paddle attachment on medium speed until the mixture is slightly sticky.
Line a baking sheet with parchment paper.
Transfer the sausage mixture in between 2 sheets of parchment paper and roll it out until it is 0.5-cm (1/4-inch) thick. Use a cookie cutter and cut out rounds (note sausage patties will shrink after cooking). Use a flat spatula and slide underneath the sausage patties, one at a time, and transfer them to the lined baking sheet in a single layer. Gather the meat scraps, roll and repeat until all the meat is used up.
Heat a non-stick frying pan over medium-high heat. You won't need any oil as the sausage patties will release oil. Place the sausage patties in a single layer into the frying pan - do not move the sausage patties - and cook until the bottom is browned. Flip the sausage patties and cook on the other side until it is browned and the patty is cooked through. Clean the frying pan if the pan has accumulated too much oil or burnt bits.
It is advisable to have some fat in the mince so the patty can be juicy. Pork or a mix of beef-pork can be used for the mince.
I listed the amount of salt in weight because sufficient amount of salt needs to be added to break down the muscle proteins. The key is to use 1 to 2% of the meat's weight. Here, I've used about 1.4 to 1.5%
To freeze: After you have mixed the ingredients together, chill for 1 hour. Squeeze the sausage mixture with your hand until the mixture is slightly sticky. Roll out the sausage mixture, cut out rounds and transfer onto a lined baking sheet in one single layer. Freeze until the sausage patties are firm, about 1 to 2 hours. Transfer the frozen sausage patties into a ziploc bag / airtight container until needed.
To cook frozen sausage patties: Do not thaw the sausage patties. Place the frozen sausage patties on the frying pan and cook over medium heat until browned on both sides and cooked through, reducing the heat if necessary.