Place the puff pastry slices next to each other and defrost. Drain tuna in a sieve. Wash the parsley, drain and pluck the leaves. Chop roughly and mix with tuna and cream cheese.
Season to taste with salt, pepper and lemon juice. Place slices of puff pastry on a floured work surface, place a shuttle form (bottom 9 x 3 cm and top 12.5 x 5 cm) on top and cut out along the top edge with a knife (2 per slice).
Place the dough sections on top of each other, roll out thinly and cut into 1 cm wide and 10 cm long strips. Brush with cream and turn each strip into a cord. Place on a baking tray lined with baking paper.
Sprinkle the sticks with sesame seeds and salt and bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 10 minutes. Grease the boat forms, place the cut puff pastry inside and bake in the preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 15 minutes.
Fall out of the moulds. Peel onion and cut into fine rings. Use 2 tablespoons to cut out cams from the cream cheese and place them on the puff pastry boats. Place the onion rings on the noodles, sprinkle with pink berries and garnish with parsley.