Heat oven to 400 degrees. On lightly
floured surface, roll out pastry and cut
into eight 4- to 5-inch squares and transfer
to greased or parchment-lined baking
sheets spaced about 1 inch apart.
Using small knife, lightly score line
1/2-inch inside edges of squares to create
framed border. With fork, prick several
holes in center of pastry squares.
Bake squares for 7-8 minutes, or
until pastry has puffed substantially,
yet not begun to brown. Remove from
oven and immediately tamp down centers
inside of scored line carefully with
back of fork.
Lightly beat 1 egg with water and brush
outside frames of pastry with egg wash.
Slightly overlapping framed pastry borders,
equally divide and arrange sausage,
asparagus and tomatoes in pastry
squares, leaving centers open for eggs.
Top each with a cracked egg, seasoning
with salt and pepper and sprinkling with
cheese, if desired. Return to oven and
bake 8-10 minutes, or until puff pastry
is golden brown and eggs have just set.
Let cool slightly and transfer tarts with
spatula to serving plate and serve warm.