Preheat oven to 350° and line two large baking sheets with parchment paper. Slice cookie dough into 1/4” rounds. Spread cookies about 1” apart on baking sheet and bake according to package instructions. Let cool completely.
Pour each color sanding sugar into a separate shallow bowl. Using scissors, cut marshmallows in half diagonally and divide halved marshmallows between bags. Dip the cut marshmallow ends in sugar.
Dye the frosting green with a couple drops of food coloring. Place a small amount of frosting on the center of each cookie and place an M&M in the center. Arrange marshmallows around the M&M to look like flower petals.
Preheat the oven to 180°C, (160°C fan, gas mark 4). Line 2 baking trays with non-stick baking paper.
Sift the flour and bicarbonate of soda into a bowl and add the rose water. Then rub the butter in the mix until it resembles breadcrumbs. Stir in the sugar.
Lightly beat the egg and golden syrup together, and then add to the flour and mix to make a dough. Leave to chill for 20 minutes.
Roll out on a lightly floured surface to ½ cm thick. Cut out with flower shaped cutters. To make the flower stem carefully insert lolly stick into the flower shaped dough, flattening the dough over the stick. Place on a baking tray, leaving a gap between them.
Bake for about 15 minutes. Leave on the tray for 10 minutes then move to a wire rack to finish cooling.
To decorate, roll out half of the white sugar paste and cut smaller flower shapes out of it. Then attach to the biscuit using a small amount of water. Colour the other half of the sugar paste icing with pink food colouring and then roll out and cut out flower shapes. Chocolate sweets such as smarties can be used as the centre of the flower. You could also simply, pipe around the outline of the cookie using designer icing and attach chocolate sweets in the centre.